9 letters · 19 points in Scrabble
noun any of various compounds that are added to gasoline to reduce engine knocking
adjective suppressing or eliminating engine knock in combustion engines
originEtymology tree Proto-Indo-European *h₂ent- Proto-Indo-European *-s Proto-Indo-European *h₂énts Proto-Indo-European *-i Proto-Indo-European *h₂énti Ancient Greek ᾰ̓ντῐ́ (ăntĭ́) Ancient Greek ἀντι- (anti-)der. English anti- English knock English antiknock From anti- + knock.
Etymology from Wiktionary, CC BY-SA 3.0