in mixed martial arts and similar sports, to tap the floor to show that you accept that your competitor has beaten you

Suddenly he dropped to his knees and tapped out. 他忽然跪倒在地，拍击地面表示认输。

to produce the rhythm of a piece of music by hitting a surface gently

He sat at the drums and tapped out the beat. 他坐在鼓边轻轻敲打拍子。

to write something using a keyboard, mobile phone, etc.

She quickly tapped out a message on her phone. 她很快地在手机上打出一条短信。