止 stop

SHE stopped you from having a good time.

Picture your foot, with her spiked heel stomping on your instep - you can't walk. You been STOPPED.

stop/cancel ★★☆☆☆ NP
中 (middle) + 止 (stop) = 中止 (stop/cancel)

(temporarily) stopped or (permanently) canceled. This is a word you'd hear in an announcement. You wouldn't say to your friend, "I'm going to 中止 watching TV for a week."

pain-killer, ★★☆☆☆
痛 (hurts!!!) + 止 (stop) = 痛み止め (pain-killer,)

pain-killer, like aspirin. (BOOBOO: not anaesthetic, which is 麻酔（ますい） )