Word Study
iambus
CIDE DICTIONARY
iambus, n. [L. iambus, Gr. ; prob. akin to to throw, assail (the iambus being first used in satiric poetry), and to L. jacere to throw. Cf. Jet a shooting forth.].
A foot consisting of a short syllable followed by a long one, as in , or of an unaccented syllable followed by an accented one, as invent; an iambic. See the Couplet under Iambic, n. [1913 Webster]
OXFORD DICTIONARY
iambus, n. (pl. iambuses or -bi) Prosody a foot consisting of one short (or unstressed) followed by one long (or stressed) syllable.
Etymology
L f. Gk iambos iambus, lampoon, f. iapto assail in words, from its use by Gk satirists
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