cheater
n. countablen. someone who acts in a dishonest way to win a game or get an advantage. You use this for people who break rules in school, sports, or relationships.
n. a person who acts dishonestly or unfairly in order to gain an advantage, especially in a game, examination, or relationship.
The teacher caught the cheater using a phone during the exam.
He was labeled a cheater after the referee discovered he had hidden a small camera to see his opponent's cards.
While some view the use of performance-enhancing drugs as a personal choice, the sporting community generally regards any athlete who bypasses regulations as a cheater who undermines the integrity of the competition.
From cheat + -er. The sense referring to welding hood lenses was inspired by cheaters (plural) as a pair of reading glasses.
From Middle English chetour, a variant of eschetour, from Old French eschetour, escheteur, equivalent to escheat + -er.
Commonly used in both academic contexts and informal discussions about romantic infidelity.