1) Friend of the groom 2) Guy in a tux with a ring 3) Guy in a tux, often 4) Ideal person at a wedding 5) Keeper of the rings 6) Member of a wedding 7) Member of a wedding party 8) Member of the wedding 9) Reception toast giver 10) Reception toaster 11) Ring bearer 12) Ring holder 13) Rite aide 14) Temporary ring holder 
[n] - the principal groomsman at a wedding
The grooms chief attendant at the wedding. Often helps the groom leading up to the big day. View our Best Man section.
Considered the principal groomsman. Often the role is filled by the most important person to the groom. 
The Best Man is usually the closest male friend or brother to the groom. Along with planning the bachelor or stag party, he makes sure the groom gets to the ceremony on time, and he is the head groomsman looking after the rest of the groomsmen, making sure they are organized. He stands beside the groom holding the rings, and makes a speech during t...
noun the principal groomsman at a wedding
the chief attendant of the bridegroom at a wedding.
A groom usually chooses a close friend or family member to be their Best Man/Woman; they traditionally organise the stag-do for the groom.