[Vocabulary] Spin off - What is the meaning ?

I am in doubt about a phrasal verb I have bumped into when reading an article in English and no dictionary in my research seem to be clear or understandable in its explanation....

...and here it is " Spin off "

And in context, it is....

Last night on TV there was this show about that actor who tries to get his big break in show biz. People thought it was a rerun but actually it was a pilot for a sitcom. It´s a spin-off of a series that was really popular some time ago. It´s a spoof of Hollywood and its stars but I thought it was way too slapstick for me. Even that famous actress, what´s her name again, had a walk-on. She had a one-liner but her acting was a show-stopper.

"It´s a spin-off of a series that was really popular some time ago".

When (usually minor) characters from one television show become the main characters in their own show, that show is called a spin-off.

seperate part,I think

winnie22 said:

separate part,I think

Click to expand...

Sorry, winnie, but I don't get that.

Please explain what you mean (and in grammatical English).

Rover