slip one's mind / memory

/slˈɪp wˈɒnz mˈaɪnd mˈɛməɹˌi/

/slˈɪp wˈʌnz mˈaɪnd mˈɛmɚɹi/

to slip one's mind / memory

(particularly of a duty or obligation) to be forgotten or disregarded

synonyms : slip

Examples

1. I'm sorry I didn't call you back sooner, it totally slipped my mind.

2. That apparently slipped my mind.

3. Additionally, you can rest assured knowing that nothing will slip your mind or fall through the cracks, as long as you keep those habits up.

4. It slipped my mind.