끼다 is fitting something into a gap or onto a part of the body — rings, gloves, an eye mask, a pen between the fingers, a plushie under the arm: 이렇게 끼는 반지 'a ring you wear like this', 안대인데 이렇게 끼고 있으면 'it's an eye mask, and if you wear it like this…'. It also means being wedged into a position: 시가총액 10위권에 아슬아슬하게 껴있는 테슬라 'Tesla clinging on inside the top ten by market cap'.