The Japanese word 'Karaoke' translates into English as 'empty .....' what?

Karaoke (a clipped compound of Japanese kara "empty" and ōkesutora "orchestra") therefore Karaoke translates to empty orchestra.

It is a form of interactive entertainment or video game in which an amateur singer sings along with recorded music (a music video) using a microphone and public address system. The music is typically an instrumental version of a well-known popular song. Lyrics are usually displayed on a video screen, along with a moving symbol, changing color, or music video images, to guide the singer. The global karaoke market has been estimated to be worth nearly $10 billion.

The concept of creating studio recordings that lack the lead vocal has been around for nearly as long as recording itself. Many artists, amateur and professional, perform in situations where a full band/orchestra is either logistically or financially impractical, so they use a "karaoke" recording; they are, however, the original artists.