Entry 2 senses Webster, 1913 oscillator /(ŏs"sĭl*lā`tẽr)/ · os·cil·la·tor · IPA /ˈɑsəlˌeɪtər/ 01 n. One that oscillates 1. One that oscillates(Electronics) 2. An instrument for measuring rigidity by the torsional oscillations of a weighted wire.(Mech.)