once; one time; one round; one game; one bout; one heat; one inning
この映画は一回見ただけでは理解できない。
You can't understand this movie by watching it just once.
一回の失敗で諦めてはいけない。
You shouldn't give up after just one failure.
週に一回は必ず掃除をしている。
I make sure to clean at least once a week.