권태기가 · 권태기를
a rut, period of boredom (especially in a relationship)
Example
결혼 3년 차에 부부에게 권태기가 찾아왔어요.
In their third year of marriage, the couple hit a rut.
Word parts
권 weary+태 idle+기 period
Literally 'a period of weariness and idleness'.
Related words