Vibrator comes from 'vibrate' + '-or' (agent suffix). 'Vibrate' is from Latin 'vibratus', past participle of 'vibrare' ('to shake, brandish, set in tremulous motion'). The historical chain includes Latin vibrare and Proto-Indo-European *weyp-. The quoted older senses, "vibrate", "-or", "Vibrate", "vibratus", and "vibrare", supply the semantic anchors for vibrator. The formation is best read as suffixal, participial, and borrowed: the word vibrator carries its older form-history into a compact English lexical shape. In present English it is used as a noun, "a device that produces a vibrating motion". Related English forms include vibrate, vibration, vibratory, and vibrant. The result is a noun whose etymology preserves both the older form and the later English specialization.