wasn't born yesterday
Definition of wasn't born yesterday
: am unlikely to believe something that is not true or to trust someone who is not trustworthy. He said he'd pay me back, but I'll believe it when I see it. I wasn't born yesterday.
Word by Word Definitions
: was not
: on the day last past : on the day preceding today
: at a time not long past : only a short time ago
: the day last past : the day next before the present
: recent time : time not long past
Seen and Heard
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