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Theodora ... thermal expansion

Theodora: Byzantine empress, wife of the emperor Justinian I (reigned 527-565), probably the most powerful woman in Byzantine history. Her intelligence and political acumen made her Justinian's most trusted adviser and ...
Theodore: antipope from September 21 to December 15, 687.
Theodore Ascidas: monk-theologian and archbishop of Caesarea in Cappadocia, who was the leading advocate of a Platonist school of Christian theology and a principal consultant at the second Council of Constantinople in ...
Theodore Bar Konai: Syrian scholar and author of a noted collection of annotations on the entire Syriac Bible. The work is also an important historical and theological source on Eastern religious sects during ...
Theodore I: pope from 642 to 649. Although noted for his generosity to the poor, he had to devote most of his pontificate to combatting Monothelitism, a heresy maintaining that Christ had ...
Theodore I Lascaris: first emperor of Nicaea, which was recognized as the Byzantine government-in-exile and as the legitimate successor of the Byzantine Empire during the Crusaders' occupation of Constantinople.
Theodore II: pope for 20 days during December 897. He was elected during one of the darkest periods in papal history, caused by the "Cadaver Synod" at which Pope Stephen VI had ...
Theodore II Lascaris: Byzantine emperor of Nicaea who-though not as capable as his grandfather or his father, Theodore I and John III Vatatzes, respectively-was an able ruler, a good soldier, and a man ...
Theodore of Canterbury, Saint: seventh archbishop of Canterbury and the first archbishop to rule the whole English Church.
Theodore Of Mopsuestia: Syrian theologian, considered the greatest biblical interpreter of his time and the spiritual head of the exegetical School of Antioch.
Theodore Of Rhaithu: theologian-monk of a monastery at Rhaithu, a port on the Sinai Peninsula, considered the last of the Neo-Chalcedonian authors. His writings sought an orthodox formulation of doctrine on the nature ...
Theodore Roosevelt National Park: area of badlands in west-central North Dakota, U.S., commemorating President Theodore Roosevelt's interest in the American West. Established as a national memorial park in 1947, it underwent subsequent boundary changes ...
Theodore Studites, Saint: also called Theodore Of Studios, or Stoudion abbot and leading opponent of iconoclasm, the doctrine opposing the veneration of religious images, which severely disturbed relations between the Byzantine and Roman ...
Theodoret Of Cyrrhus: Syrian theologian-bishop, representative of Antioch's historico-critical school of biblical-theological interpretation, whose writings were a moderating influence on the 5th-century Christological disputes and contributed to the development of the Christian theological ...
Theodoric: king of the Ostrogoths (from 471), who invaded Italy in 488 and completed the conquest of virtually the entire peninsula and Sicily by 493, making himself king of Italy (493-526) ...
Theodoric: antipope from 1100 to 1102. As cardinal bishop of Santa Ruffina, he was elected pope by the faction headed by the Holy Roman emperor Henry IV during the struggle between ...
Theodoric I: Merovingian king of Reims from 511. Theodoric was the eldest son of Clovis I, but born of an unknown woman, unlike the other sons, whose mother was Clotilda. An able ...
Theodoric II: younger son of the Merovingian Childebert II; he succeeded his father as king of Burgundy in 595. Cooperation with his brother, Theodebert II of Austrasia, was followed by discord, and ...
Theodoric III: Merovingian ruler who succeeded his brother Chlotar III as king of Neustria and Burgundy in 673, at the instigation of Ebroin, the Neustrian mayor of the palace. He was soon ...
Theodoric IV: penultimate ruler of the Merovingian dynasty, the son of Dagobert III; he was king of the Franks from 721. A puppet who was controlled by Charles Martel, the grandfather of ...
Theodoric, Mausoleum of: tomb built c. 520 in Ravenna, Italy, by the Arian Ostrogothic emperor Theodoric. The lower story is a decagon, while the upper story is circular and roofed with a remarkable ...
Theodorus Lector: English Theodore The Reader Greek church historian, author of two significant epitomes of Byzantine history correlating data from leading 5th-century chroniclers, and constituting an essential source for events of that ...
Theodosius I: Roman emperor of the East (379-392) and then sole emperor of both East and West (392-395), who, in vigorous suppression of paganism and Arianism, established the creed of the Council ...
Theodosius I Boradiotes: Greek Orthodox patriarch of Constantinople (1179-83), inflexible opponent of the Muslim religion, critic of union with the Latin Church of the West, and guardian of Orthodox morality at the Byzantine ...
Theodosius II: Eastern Roman emperor from 408 to 450. He was a gentle, scholarly, easily dominated man who allowed his government to be run by a succession of relatives and ministers.
Theodosius III: Byzantine emperor from 715 to 717. He was an obscure tax collector of southwestern Asia Minor who against his will was proclaimed emperor by the troops of the Opsikion theme ...
Theodosius Of Alexandria: patriarch of Alexandria (535-566), theologian, and leader of the Monophysites in Egypt and Syria, who were reputed for their asceticism and also for their mystical prayer.
Theodosius of Palestine, Saint: a principal proponent of orthodoxy in the Christological controversy (a dispute centring on the nature and person of Christ) and one of the fathers of Palestinian monasticism.
Theodossia: genus of extinct brachiopods (lamp shells) the fossils of which are restricted to Early Devonian marine rocks (the Devonian period occurred from 408 million to 360 million years ago). The ...
Theodotion: Hellenistic Jewish scholar and linguist and author of a Greek translation of the Old Testament. According to two early Christian writers of the 2nd and 4th centuries, Theodotion probably came ...
Theodotus Of Ancyra: theologian, bishop of Ancyra, and a leading advocate of orthodoxy in the discussion of the nature and Person of Christ at the Council of Ephesus in 431. Theodotus was a ...
Theodotus The Gnostic: a principal formulator of Eastern Gnosticism, a system of religious dualism (belief in rival deities of good and evil) with a doctrine of salvation by gnosis, or esoteric knowledge.
Theodotus The Tanner: principal exponent at Rome of the heresy of Adoptionism (see Monarchianism).
Theodulf Of Orleans: prelate, poet, and one of the leading theologians of the Frankish Empire.
Theodurus Abu Qurrah: Syrian Melchite bishop, theologian, and linguist, early exponent of cultural exchange with Islamic and other non-Christian peoples, and the first known Christian writer in Arabic.
Theognis: elegiac poet, many of whose poems were addressed to his beloved, one Cyrnus. Theognis' poems were also much concerned with good breeding and are important for their portrayal of aristocratic ...
Theognostos: Byzantine monk, theologian, and chronicler, coauthor of a report on the situation of the Eastern Church during the turbulent reign of Photius (858-867 and 878-886), the controversial patriarch of Constantinople. ...
Theognostus Of Alexandria: Greek theologian, writer, and prominent head of Alexandria's Catechetical school, at that time the intellectual centre for Hellenistic Christianity. Reputed to be one of the Greek Church's distinguished teachers, Theognostus ...
Theoleptus Of Philadelphia: Greek Orthodox metropolitan of Philadelphia and theological polemicist and writer on Christian asceticism, who emerged as a central figure in the political and theological turmoil of his age.
theological liberalism: a form of religious thought that establishes religious inquiry on the basis of a norm other than the authority of tradition. It was an important influence in Protestantism from about ...
theology: discipline of religious thought that is restricted in its narrower sense, because of origination and format, to Christianity, but in its broader sense, because of its themes, to other religions. ...
theology: discipline of religious thought that is restricted in its narrower sense, because of its origination and format, to Christianity but that may be applied in a broader sense, because of ...
Theophanes the Confessor, Saint: Byzantine monk, theologian, and chronicler, a principal adversary of the heterodox in the Iconoclastic Controversy (concerning the destruction of sacred images). The annals he wrote are the leading source for ...
Theophanes The Greek: one of the leading late Byzantine painters of murals, icons, and miniatures who influenced the 15th-century painting style of the Novgorod school (q.v.) and the Moscow school (q.v.). His early ...
theophany: (from Greek theophaneia, "appearance of God"), manifestation of deity in sensible form. The term has been applied generally to the appearance of the gods in the ancient Greek and Near ...
Theophilus: Eastern Roman emperor (829-842), principal promoter of the 9th-century Byzantine renascence of learning, and the last advocate of the Eastern heresy of Iconoclasm (the destruction of religious images) in a ...
Theophilus: German monk who wrote De diversis artibus (c. 1110-40; also called Schedula diversarum artium), an exhaustive account of the techniques of almost all the known crafts of the first half ...
Theophilus of Alexandria, Saint: theologian and patriarch of Alexandria, Egypt, violent opponent of non-Christian religions, severe critic of heterodox influence among Christian writers and monks, and a major figure in the ecclesiastical politics of ...
Theophrastus: Greek Peripatetic philosopher and pupil of Aristotle. He studied at Athens under Aristotle, and when Aristotle was forced to retire in 323 he became the head of the Lyceum, the ...
Theophylactus Of Ochrida: Greek Orthodox archbishop of Ochrida (modern Ohrid, Macedonia), theologian and linguistic scholar, who helped disseminate Byzantine culture among the Balkan Slavs during the early Middle Ages.
Theophylactus Simocattes: also spelled Theophylact Simocatta Byzantine historian whose chronicles of the Eastern Roman Empire provide a unique source for the Greek relations with the Slavs and Persians during the 6th and ...
theophylline: alkaloidal drug used in medicine as an antiasthmatic, coronary vasodilator, and diuretic. Theophylline is a xanthine alkaloid, a methylxanthine chemically related to caffeine and theobromine. Along with caffeine, it is ...
Theopompus Of Chios: Greek historian and rhetorician whose Philippica, though lost in original, has survived through the work of later writers to form one element in the tradition concerning the reign of Philip ...
theorbo: large bass lute, or archlute, used from the 16th to the 18th century for song accompaniments and for basso continuo parts. It had six to eight single strings running along ...
Theorell, Axel Hugo Teodor: Swedish biochemist whose study of enzymes that facilitate oxidation reactions in living cells contributed to the understanding of enzyme action and led to the discovery of the ways in which ...
theorem: in mathematics and logic, a proposition or statement that is demonstrated. In geometry, a proposition is commonly considered as a problem (a construction to be effected) or a theorem (a ...
theosophy: religious philosophy with mystical concerns that can be traced to the ancient world but that has been of catalytic significance in religious thought in the 19th and 20th centuries. The ...
Theotokas, Yorgos: Greek novelist known for his clarity of expression and civilized writing.
Theotokos: (Greek: "God-Bearer"), in Eastern Orthodoxy, the designation of the Virgin Mary as mother of God. The term has had great historical importance because the Nestorians, who stressed the independence of ...
Thera: island, southernmost island of the Cyclades group, Greece, in the Aegean Sea, sometimes included in the Southern Sporades group. The island has an area of 29 square miles (76 square ...
theralite: any member of a group of intrusive igneous rocks that contain labradorite (basic plagioclase feldspar), nepheline, and titaniferous augite. Theralites are classified in the nepheline-tephrite group in this series (see ...
Theramenes: Athenian politician and general, active in the last years of the Peloponnesian War (431-404 BC) and controversial in his own lifetime and since. His father, Hagnon, a contemporary of Pericles, ...
Therapeutae: Jewish sect of ascetics closely resembling the Essenes, believed to have settled on the shores of Lake Mareotis in the vicinity of Alexandria, Egypt, during the 1st century AD. The ...
therapeutics: treatment and care of a patient for the purpose of both preventing and combating disease or alleviating pain or injury. The term comes from the Greek therapeutikos, which means "inclined ...
therapsid: any member of a major order (Therapsida) of reptiles of Permian and Triassic time (from 286 to 208 million years ago). Therapsids were the stock that gave rise to mammals. ...
Theravada: major form of Buddhism prevalent in Sri Lanka (Ceylon), Myanmar (Burma), Thailand, Cambodia, and Laos.
theremin: electronic musical instrument invented in 1920 in the Soviet Union by Leon Theremin (also called Lev Termen). It consists of a box with radio tubes producing oscillations at two sound-wave ...
Therese of Lisieux, Saint: Carmelite nun whose service to her Roman Catholic order, although outwardly unremarkable, was later recognized for its exemplary spiritual accomplishments. She was named a doctor of the church by Pope ...
Theresienstadt: town in northern Bohemia (now in the Czech Republic), founded in 1780 and used from 1941 to 1945 by Nazi Germany as a walled ghetto, or concentration camp, and as ...
Theriault, Yves: one of the most prolific writers in Canada, with some 1,300 radio and television scripts and some 50 books to his credit. He was hailed as a literary genius after ...
thermae: complex of rooms designed for public bathing, relaxation, and social activity that was developed to a high degree of sophistication by the ancient Romans. Although public baths are known to ...
Thermai, Gulf of: large gulf of the Aegean Sea in northeastern Greece between Thessaly, Macedonia, and the Chalcidice peninsula. Up to 60 mi (100 km) long northwest-southeast and about 40 mi wide at ...
thermal: current of air rising from a locally hot patch of ground. See updraft and downdraft.
thermal conduction: transfer of energy (heat) arising from temperature differences between adjacent parts of a body.
thermal energy: internal energy present in a system in a state of thermodynamic equilibrium by virtue of its temperature. Thermal energy cannot be converted to useful work as easily as the energy ...
thermal expansion: the general increase in the volume of a material as its temperature is increased. It is usually expressed as a fractional change in dimensions or volume per unit temperature change; ...