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-ative

a combination of -ate1 and -ive, used to form adjectives from stems in -ate1 (regulative); on this model, because of the frequency and productivity of -ate1, used independently to form adjectives from stems of other origin: normative.

Origin of -ative

< Latin -ātīvus, equivalent to -āt(us) -ate1 + -īvus -ive
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British Dictionary definitions for -ative

-ative

suffix forming adjectives

of, relating to, or tending toauthoritative; decorative; informative

Word Origin for -ative

from Latin -ātīvus, from ātus -ate 1 + īvus -ive
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
Word Origin and History for -ative

word-forming element meaning "of or related to; tending to," from Latin -ativus.

Online Etymology Dictionary, © 2010 Douglas Harper