轮
lún · HSK 4
to take turns
🎡 轮 = 车 (vehicle) + 仑 (order); a wheel turns in order, hence 'a round/turn'
As a measure word, 轮 counts rounds or turns of recurring events — a round of talks, a round of drinks. The wheel radical 车 anchors the 'cycle/rotation' sense behind each 'round'.
轮 — car radical 车 + 仑 (phonetic)
轮 is a semantic-phonetic compound. The left side 车 (chē, 'cart/vehicle') gives the meaning, since 轮 originally referred to a wheel. The right side 仑 supplies the sound 'lún'. From 'wheel' it extended to related senses like 'rotate', 'take turns', and 'round'.