be on the tip of your tongue
US /bi ɑn ðə tɪp əv jʊər tʌŋ/
UK /bi ɑn ðə tɪp əv jʊər tʌŋ/
1.
almost able to remember something, but not quite
:
•
Her name is on the tip of my tongue, but I just can't recall it.
•
I know that actor's name, it's on the tip of my tongue!