IPA: /ˈdɔːɡˌfaɪtə/
KK: /ˈdɔgˌfaɪtər/
A person who participates in the illegal practice of training dogs to fight each other for entertainment or profit.
The authorities arrested several individuals involved in dogfighting, including a notorious dogfighter.
Dogfighter → It is formed from "dog" (of uncertain origin, possibly from Old English *docga*, meaning a powerful breed of dog) and "fighter" (from Old English *feohtan*, meaning to fight). The word "dogfighter" refers to someone who engages in the act of fighting dogs, typically in a cruel and illegal manner.
Think of a person who is involved in the act of 'fighting' ('fighter') with 'dogs' — that's why a dogfighter is someone who fights dogs.