What does “거짓말하지 마” mean in Korean?

거짓말하지 마 means “don’t lie,” but between friends it lands more like “no way!” or “stop it!” — the mock-disbelief you fire back at a compliment too good to be true. The real lesson is the ending: take any 하다 verb, swap 하다 for 하지 마, and you’ve built a casual “don’t do it.” 거짓말하다 (to lie) becomes 거짓말하지 마 (don’t lie). (Standard spelling closes 거짓말하다 up; you’ll also see it spaced as 거짓말 하다.)

The pattern is verb stem + 지 마, where 마 is the blunt, intimate form of the auxiliary 말다 (“to stop/refrain”). Dial the politeness up by lengthening it: 하지 마 (to a close friend) → 하지 마요 → 하지 마세요 (polite) → 하지 마십시오 (formal). It works on any verb — 가지 마 (“don’t go”), 울지 마 (“don’t cry”). In this clip the line ricochets back and forth as the friends tease each other, the textbook setting for its half-serious “yeah, right” tone rather than a literal accusation.