This is the 17684th most frequent Korean word.
소대가리
"소대가리" means "cow's head" and can also be used figuratively as an insult implying foolishness or dullness.
Here, '소대가리' is used literally to describe the head of a cow.
소대가리가 움직이지 않았다.
The cow's head did not move.
The phrase '소대가리 같아서' metaphorically compares the person to a cow's head, implying stubbornness, as cow heads are seen as unyielding.
너는 소대가리 같아서 고집이 세다.
You are stubborn like a cow's head.
The usage of '소대가리 같아서' figuratively suggests that the problem is tough or rigid, likening its complexity or stubborn nature to that of a cow's head.