adverb, adverb taking the 'to' particle
collapsing; slumping down; lacking strength to stand
Describes a person or thing losing strength and sinking to the ground, often from exhaustion, shock, or weakness. Commonly used with と and verbs like 座り込む or 倒れる.
疲れてへたへたと座り込んだ。
Exhausted, I slumped down to the ground.
ショックでその場にへたへたと倒れた。
In shock, she collapsed on the spot.