EXTERMINATOR

exterminator, terminator, eradicator

(noun) someone who exterminates (especially someone whose occupation is the extermination of troublesome rodents and insects)

Source: WordNet® 3.1

Noun

exterminator (plural exterminators)

Someone or something that exterminates.

Specifically, a person whose job it is to kill insects and other pests in a building.

Source: Wiktionary

Ex*ter"mi*na`tor, n. Etym: [L.]

Definition: One who, or that which, exterminates. Buckle.

Source: Webster’s Unabridged Dictionary 1913 Edition