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legion

(Encyclopedia)legion, large unit of the Roman army. It came into prominence c.400 b.c. It originally consisted of 3,000 to 4,000 men drawn into eight ranks: the first six ranks, called hoplites, were heavily armed,...

Americanization

(Encyclopedia)Americanization, term used to describe the movement during the first quarter of the 20th cent. whereby the immigrant in the United States was induced to assimilate American speech, ideals, traditions,...

Déby, Idriss

(Encyclopedia)Déby, Idriss ĭdrĭsˈ dĕbēˈ [key], 1952–2021, Chadian military and political leader, president ...

cytosine

(Encyclopedia)cytosine sīˈtōsēnˌ [key], organic base of the pyrimidine family. It was isolated from the nucleic acid of calf thymus tissue in 1894. A suggested structure for cytosine, published in 1903, was co...

water beetle

(Encyclopedia)water beetle, name for aquatic beetles of several families. They should not be confused with water bugs, which are true bugs (order Hemiptera). The predaceous diving beetles (family Dytiscidae) are a ...

tektite

(Encyclopedia)tektite tĕktīt [key], naturally occurring, silica-rich (65%–80% SiO2) glass resembling obsidian and sometimes shale, and is normally jet black to olive green. They appear as small rounded or elong...

zaibatsu

(Encyclopedia)zaibatsu zīˈbätso͞o [key] [Jap.,=money clique], the great family-controlled banking and industrial combines of modern Japan. The leading zaibatsu (called keiretsu after World War II) are Mitsui, M...

Boolean algebra

(Encyclopedia)Boolean algebra bo͞oˈlēən [key], an abstract mathematical system primarily used in computer science and in expressing the relationships between sets (groups of objects or concepts). The notational...

kwashiorkor

(Encyclopedia)kwashiorkor kwăshˌēôrˈkôr [key], protein deficiency disorder of children. It is prevalent in overpopulated parts of the world where the diet consists mainly of starchy vegetables, particularly i...

l-dopa

(Encyclopedia)l-dopa ĕl-dōˈpə [key], drug used to alleviate some of the symptoms of Parkinson's disease, particularly trembling, rigidity, and slow movements; the drug is also called levodopa. Parkinson's disea...