11 letters · 16 points in Scrabble
adjective serving to instruct or enlighten or inform
originEtymology tree English instruct Proto-Indo-European *-wós Proto-Indo-European *-iHwósder. Latin -īvus Old French -ifbor. Middle English -yf English -ive English instructive From instruct + -ive.
Etymology from Wiktionary, CC BY-SA 3.0