best man

US /ˌbest ˈmæn/
UK /ˌbest ˈmæn/
"best man" picture
1.

padrino

a male friend or relative who attends the bridegroom at a wedding, and is usually his chief attendant

:
My brother asked me to be his best man at his wedding.
Mi hermano me pidió que fuera su padrino en su boda.
The best man gave a funny speech at the reception.
El padrino dio un discurso divertido en la recepción.