Senses
一轮/ 一輪 one round
a complete cycle or circuit of an activity; a turn around a group
一轮/ 一輪 [for round objects]
Used as a measure word for round things like the sun or a bright moon.
一轮/ 一輪 first round
the first stage or round of a match, election, series of talks, or policy
一轮/ 一輪 [for twelve-year cycle]
A period of twelve years, corresponding to the cycle of the twelve Chinese zodiac signs.