Times
Number Of Times, Time
counter
The kanji and the word are exactly the same. That means they share meanings as well.
The reading is the on'yomi reading which you learned with the kanji. This is probably because this word gets attached to numbers usually, which makes it behave more like jukugo. So, you can have 1回, 2回, 3回, or even 100回 if you're into that sort of thing.
二回
twice
三回
three times
一回
once
今日はテレビを一回だけ見た。
I only watched TV once today.
これは犬用のボール。赤ちゃんのボールじゃないって、何回言ったら分かるの?
This ball is for dogs. How many times do I have to tell you that it's not a ball for a baby?
ファーストキスは人生で一回しかない大切なものなんだよ。
Your first kiss is an important event you only get to experience once in your life.