borrowed clothes
Refers to clothing that one has borrowed from someone else. Not a high-frequency word, but straightforward in meaning.
Today I went to the party in clothes borrowed from a friend.
急な雨で、彼女の借り着を着て帰った。
Because of the sudden rain, I went home wearing her borrowed clothes.
Compound of 借り (kari, 'borrowing') + 着 (gi, 'clothing'). The reading ぎ is a rendaku form of き.