함정 means ‘But there is something bad, that is..’
a good thing is at front of sentence that included this word, and then bad thing shows with this word. For instance, ‘I bought a new cell phone yesterday'(good thing) , It’s 함정 that is broken today.(bad thing is showed with 함정)
Originally, 함정 means a trap.
Definition by other languages
먼저 좋은 상황을 소개하고, 그에 대비하여 그 상황에 무언가 안좋은 점이 있을때 쓰는 단어.
나 새차 샀다. 근데 256개월 할부라는게 함정.