Meaning of “have a senior, blond, etc moment” - Learner’s Dictionary

have a senior, blond, etc moment

informal

to behave, for a short time, in a way that shows you are old, silly, etc:

I've just had a senior moment -- I couldn't remember why I'd gone into the kitchen.

(Definition of “have a senior, blond, etc moment” from the Cambridge Learner’s Dictionary © Cambridge University Press)