"catch some Z's"的定义和意义

What is the origin of the idiom "catch some Z's" and when to use it?

The idiom "catch some Z's" is derived from the practice of representing sleep with the letter "Z" in comic strips and cartoons, dating back to the early 20th century. The letter "Z" resembles the visual representation of someone asleep, complete with the Z-shapes rising from their slumbering form. It is often employed to express the need for rest or relaxation, whether it's to combat tiredness, recover from a long day, or rejuvenate oneself.