nursery school graduate; person who attended nursery school instead of kindergarten
Internet slang, often derogatory or jocular. Used to label someone who went to a nursery school (保育園) rather than a kindergarten (幼稚園), implying a perceived difference in upbringing or social background. Compare ヨウ卒 (kindergarten graduate).
See also: 幼卒
I got annoyed when someone online said, 'Nursery school grads have no manners.'
That person went to nursery school, so they go quiet when the topic turns to kindergarten.