IPA: /ˈkɪdˌnæpər/
KK: /ˈkɪdˌnæpər/
A person who takes someone away illegally, often for ransom or other demands.
The police arrested the kidnapper before he could escape with the victim.
Kidnapper → It is formed from "kid" (from Middle English *kidde*, meaning a young goat or child) and "nap" (from the dialectal English *napper*, meaning to seize or snatch). The word "kidnapper" refers to someone who seizes or snatches a child.
Think of someone who 'snatches' ('nap') a 'child' ('kid') — that's why a kidnapper is someone who takes a child.