"Hair of the Dog" is the title track of Nazareth's 1975 album Hair of the Dog. It is sometimes called "Son of a Bitch" because of the repeated lyric in the hook ("Now you're messing with a son of a bitch"). The song is about a charming and manipulative woman who can get men to acquiesce to her every need. The singer is letting her know that she has met her match in him, a self-described "son of a bitch." "Hair of the Dog" uses a talk box extensively during its bridge. The song's title, which does not appear in the lyrics, is a pun ("hair of the dog" = "heir of the dog" = "son of a bitch").