Just imagining the Hungarian dubbing of "The Office" (US Version). Dwight: "Hamis!"
Hamis! should have been highlighted; it is a new word.
Hamis has several synonyms in English: False, untrue, not true, etc. They should all be acceptable.
The word "hamis" does literally translate to "false", but it is not traditionally used in this way in Hungarian. A better Hungarian translation for "False!" in this context would be "Tévedés!" (literally 'error, mistake; the act of being wrong').