Be Born Yesterday Meaning
(idiomatic, informal) To be new, naive, innocent, inexperienced, or easily deceived.
Example: I was not born yesterday, you know. I have done this before!
1915, William MacLeod Raine, Steve Yeager, ch. 6:
"Say, do I look like I was born yesterday? See any green in my eye, Cactus Center?"
1998, Gwyn Hyman Rubio, Icy Sparksâ€Ž, page 155:
"Compared to me, you were born yesterday."
2005, Howard Zinn and Donaldo Pereira Macedo, Howard Zinn on Democratic Educationâ€Ž, page 69:
If you don't know important things about history, then it's as if you were born yesterday.