Tetrad

• POS: Noun
• HYPHEN: tet=rad

CIDE DICTIONARY

Tetrad, n. [L. tetras, -adis, Gr. , : cf. F. tétrade.].

•  The number four; a collection of four things; a quaternion.  [1913 Webster]
•  A tetravalent or quadrivalent atom or radical; as, carbon is a tetrad.  [1913 Webster]

OXFORD DICTIONARY

Tetrad, n.
1 a group of four.
2 the number four.

Etymology

Gk tetras -ados (as TETRA-)

ROGET THESAURUS

Tetrad

Four

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