a group of three people or things

There was disappointment for the trio of 200 metre runners, all of whom failed to reach the final. 我们参加200米跑的3位选手都很令人失望，没有一个人进入决赛。

a group of three musicians or singers who perform together

Many jazz trios consist of piano, guitar, and double bass. 许多爵士三重奏均由钢琴、吉他和低音提琴组成。

a piece of music that has been written to be performed by three people

The final item on today's programme is Beethoven's Trio in B flat. 今天的最后一个曲目是贝多芬的三重奏曲，降B调。