I've worked here all of my 'adult life'. [=I've worked here since I became an adult]
People who are close friends as children aren't always friends as 'adults'.
The university offers a popular program of 'adult education'.
(..) Penny's pregnant, too? You're the other baby. Oh, really? Okay, well, would a baby have to shave once every days? Would an adult refuse to eat his graham crackers because one of them was broken? I guess we'll call this a draw. So, I'm glad you guys are here. (..)2016 TvShow: The Big Bang Theory Title: The Positive Negative Reaction Season: 9 Episode 16