turn-on (Noun) — Something causing excitement or stimulating interest.
turn-on (Verb) — Cause to operate by flipping a switch. ex. "turn on the stereo"
turn-on (Verb) — Be contingent on.
turn-on (Verb) — Produce suddenly or automatically. ex. "Turn on the charm" ex. "turn on the waterworks"
turn-on (Verb) — Become hostile towards. ex. "The dog suddenly turned on the mailman"
turn-on (Verb) — Cause to be agitated, excited, or roused.
turn-on (Verb) — Stimulate sexually. ex. "This movie usually turns on the male audience"
turn-on (Verb) — Get high, stoned, or drugged. ex. "He turns on every weekend"