counter for occurrences; times
Used after a number to count how many times something happens. Also used for ordinal numbering of events (e.g., 第1回).
I've already seen this movie three times.
The fifth meeting is next week.
Used as a noun meaning a particular occurrence or turn. Often appears in set phrases like その回 or 今回.
That class session was canceled.
This time's project is very interesting.
Colloquial use for a serialized episode, chapter, or installment of a story, drama, or series.
This drama has 12 episodes in total.
I'm looking forward to the next chapter of the manga.
Abbreviation of 回族. Refers to the Hui ethnic group in China.
See also: 回族
The Hui are one of China's ethnic minorities, sometimes abbreviated as 回.
Abbreviation of 回教. An older term for Islam, now less common.
See also: 回教
回教 is an old term for Islam, sometimes abbreviated as 回.
He brushes his teeth three times a day.
The 10th Olympic Games were held.
This is my third attempt.
He got better with each successive practice session.
回 simply counts the number of occurrences (三回 = three times), while 回目 specifies which occurrence in order it is (三回目 = the third time).
回 is the plain, general counter for occurrences or innings, whereas 回戦 specifically counts rounds within a knockout competition and cannot be used for unrelated repeated events.