introspective (adj.)

1670s, "action of closely inspecting or examining," noun of action from past participle stem of Latin introspicere "to look into, look at, examine, observe attentively," from intro- "inward" (see intro-) + specere "to look at" (from PIE root *spek- "to observe"). Meaning "action of searching one's feelings or thoughts" is from 1807.

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).