Answer:

gloater

Answer	Crossword Clue
GLOATER	"I told you so!" type
GLOATER	"Nyah nyah!" type
GLOATER	Ungracious winner

GLOATER	He told you so
GLOATER	Bad winner
GLOATER	Unpleasant opponent

Crossword

a puzzle consisting of a grid of squares and blanks into which words crossing vertically and horizontally are written according to clues.