Definition of crown:
a reward of victory or a mark of honor
; a royal
, imperial or princely headdress; a diadem
of, related to, or pertaining to a crown; of, related to, pertaining to the top of a tree
to place a crown on the head of; to formally declare (someone) a king
"the mother was in the second stage of labor and the fetus had just crowned, prompting a round of encouragement from the midwives."