Meaning of the word "slip one's mind" in English

What does "slip one's mind" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

slip one's mind

US /slɪp wʌnz maɪnd/
UK /slɪp wʌnz maɪnd/
"slip one's mind" picture

Idiom

to be forgotten by someone

Example:
I'm sorry I didn't call you; it completely slipped my mind.
I meant to buy some milk, but it slipped my mind.