What does catch some z's mean? What are z's?

[Znazzy]

English Idioms and Expressions, Advanced Level

ESL/EFL Test #28 "American Slang Words (2)", question 1

Lauren moved to Los Angeles to become an actress. Now, she's working as a waitress and waiting for a lucky break.

(a) a broken limb
(b) an inheritance settlement
(c) a great opportunity to further her career

English Idioms and Expressions, Advanced Level

ESL/EFL Test #28 "American Slang Words (2)", answer 1

Lauren moved to Los Angeles to become an actress. Now, she's working as a waitress and waiting for a great opportunity to further her career.

Correct answer: (c) a great opportunity to further her career
_________________________

catch some z's . What does mean z's ?

[MrPedantic]

Hello Z.,

It means "to get some sleep", "to take a nap".

Best wishes,

MrP