di·gam·ma
(dī-găm′ə)n. A letter occurring in certain early forms of Greek and transliterated in English as w.
[Latin, from Greek : di-, two; see di-1 + gamma, gamma (because its shape resembles two gammas); see gamma.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
digamma
(daɪˈɡæmə) n (Letters of the Alphabet (Foreign)) a letter of the Greek alphabet (Ϝ) that became obsolete before the classical period of the language. It represented a semivowel like English W and was used as a numeral in later stages of written Greek, and passed into the Roman alphabet as F
[C17: via Latin from Greek, from di-1 + gamma; from its shape, which suggests one gamma upon another]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
di•gam•ma
(daɪˈgæm ə)
n., pl. -mas. a letter of the early Greek alphabet that represented a sound similar to English w and fell into disuse before the classical period.
[1545–55; < Latin < Greek dígamma]
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