Word Study
octa-
CIDE DICTIONARY
octa-,
A prefix meaning eight . See Octo-. [1913 Webster]
octa-, [L. octo eight, Gr. 'oktw`, with a combining form 'okta-. Cf. Eight.].
A combining form meaning eight ; as in octodecimal, octolocular. [1913 Webster]
OXFORD DICTIONARY
octa-, comb. form (also oct- before a vowel) eight.
Etymology
Gk okta- f. okto eight
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