Moaning Min ‧ nie BrE AmE , moaning Minnie /ˌməʊnɪŋ ˈmɪni/ noun
1 . informal someone who is never satisfied and is always complaining
2 .
a) in World War II, the name of a German weapon that made a ↑ scream ing noise when it was fired
b) in World War II, a name for the ↑ siren (=machine that makes a long, loud warning sound) that warned people that enemy planes were about to drop bombs