the prefix a- or, before a vowel, an-, used in Greek and English to express negation or absence.
Origin of alpha privative
First recorded in 1580–90
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British Dictionary definitions for alpha privative
(in Greek grammar) the letter alpha (or an- before vowels) used as a negative or privative prefix. It appears in English words derived from Greek, as in atheist, anaesthetic
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012