1640s, from Latin instinct-, past participle stem of instinguere "to incite, impel" (see instinct) + -ive. Related: Instinctively (1610s); instinctiveness. Coleridge uses instinctivity.
Entries linking to instinctive
instinct n.
early 15c., "a prompting" (a sense now obsolete), from Old French instinct (14c.) or directly from Latin instinctus "instigation, impulse, inspiration," noun use of past participle of instinguere "to incite, impel," from in- "into, in, on, upon" (from PIE root *en "in") + stinguere "prick, goad," from PIE *steig- "to prick, stick, pierce" (see stick (v.)).
Meaning "animal faculty of intuitive perception" is from mid-15c., from notion of "natural prompting." General sense of "natural tendency" is first recorded 1560s.
Instinct is said to be blind--that is, either the end is not consciously recognized by the animal, or the connection of the means with the end is not understood. Instinct is also, in general, somewhat deficient in instant adaptability to extraordinary circumstances. [Century Dictionary]
-ive
word-forming element making adjectives from verbs, meaning "pertaining to, tending to; doing, serving to do," in some cases from Old French -if, but usually directly from Latin adjectival suffix -ivus (source also of Italian and Spanish -ivo). In some words borrowed from French at an early date it has been reduced to -y (as in hasty, tardy).