A device, system, or person that works to prevent or detect cheating in games, competitions, or tests.
Anti- + cheater (one who cheats). Cheater comes from Old English 'cheat' (to deceive). The prefix anti- creates an agent noun for something opposing cheaters. This term is modern, reflecting gaming and testing culture.
Video game companies employ teams of 'anticheaters'—people hunting bots and code-breakers in real time—it's digital arms race that would baffle someone from a century ago but makes perfect sense now.
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