12 letters · 29 points in Scrabble
noun an instrument that indicates whether two periodic motions are synchronous (especially an instrument that enables a pilot to synchronize the propellers of a plane that has two or more engines)
originEtymology tree English synchronize Proto-Indo-European *-yósder. Proto-Italic *-āzijos Latin -āriusnom. Latin -āriusbor. Proto-Germanic *-ārijaz Proto-West Germanic *-ārī Old English -ere Middle English -ere English -er English synchronizer From synchronize + -er.
Etymology from Wiktionary, CC BY-SA 3.0