: an informal session of group singing of popular or folk songs : songfest
People who had brought their guitars led spontaneous sing-alongs in the hotel lobby.The New Yorker
Old-fashioned hayrides and sing-alongs in front of a campfire … Mary Beth Giles
Audience participation is one of the things that has made the show a success, and there will, again, be plenty of opportunity to take part in the sing-alongs.Canadian Motorist
also: a song appropriate for a sing-along
A guy from the wedding party joined the band for the Garth Brooks classic sing-along "Friends in Low Places" and knocked it out of the park. Luke Vose