Well yes, it's a figure of speech, but not something that actually exits in reality. You have a shaft (bolt) of lightning pulled to earth ground (Speed of light), followed by a clap of thunder (speed of sound). I maintain there is no such thing as a bolt of thunder in the real world. There can be no thunder without lightning happening first. In a song lyric "Thunderbolts and lightning" sounds better than "Lightning and Thunderbolts", and Thunderbolts doesn't rhyme with "frightening". "Lightning and Thunder" has been used in lyrics. It works well, and is also chronologically correct. For some reason people say "Thunder and Lightning" instead of "Lightning and Thunder". Possibly because they always hear the thunder, but inside a building you may not see the lightning bolt which always comes first.
Ah yes but we generally refer to the storms as Thunder Storms not Lightning Storms, so a bolt that was the product of such a storm and that caused thunder could be called a Thunder Bolt. The event itself causes both light and sound so 'bolt' could apply to either.
Anyway, I think they should have named it Thunder Clap, as it has proven to be about as popular as 'The Clap' !