Meaning of the word whatsit in English

What does whatsit mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

whatsit

US /ˈwɑːt.sɪt/
UK /ˈwɒt.sɪt/

Noun

a thing whose name one has forgotten or does not know

Example:
Can you pass me that whatsit over there?
I need to fix the whatsit on the engine.