Singing without a live orchestra or band. Originally meaning "without orchestra," it is a combination of Japanese "kara" meaning "empty/bare-handed" as in "karate", and the "okee" sound from the first syllable of "orchestra" as pronounced by Japanese.
The guy who thought up karaoke created a bar owner's dream, because as patrons provide their own entertainment by singing along with a machine, management saves a fortune by not hiring talented musicians.
A kind of backwards talent contest where the aim is to sing to sing other peoples songs as badly as possible.
The true losers in karaoke are the people who try hardest.