Refers to the third molar, typically emerging in late teens or early adulthood. Often used in medical or everyday contexts.
My wisdom tooth hurt, so I went to the dentist.
I had surgery to remove my wisdom tooth.
not knowing one's birth parents; person who does not know their birth parents
Literally 'not knowing one's parents'. Can refer to the state of being unaware of one's biological parents, or a person in that situation. Often used in discussions of adoption or orphanhood.
He grew up not knowing his birth parents.
There is an organization that supports children who do not know their birth parents.