groomsman
/ˈɡruːmzmen/Definitions
1. noun
A man who acts as a companion to the groom at a wedding.
“The groomsman stood by the groom’s side as he exchanged vows with his bride.”
2. noun
A man who is a member of a group or party, especially in a formal or ceremonial context.
“The groomsman was a member of the wedding party and helped organize the reception.”