쇠뿔도 단김에 빼라
bull’s-horn-TOO at-once dodge-COMMAND
Dodge the bull’s horn at once.
“Strike while the iron is hot” is the translation offered for this expression on various websites and Korean-English dictionaries. I don’t like how no one tries to actually translate the literal meaning of the proverb – they just offer “Strike while the iron is hot.” But there’s no striking, no iron, no hotness – not in the actual Korean proverb. What there is is a bull’s horn and some kind of dodging or evading or removing. 단김에 seems to be a variant of 단결에 “in a body, in combination, in solidarity” and therefore “at once.”