Answer:

impostor

Answer	Crossword Clue
IMPOSTOR	Quack
IMPOSTOR	Pretender
IMPOSTOR	Fake

IMPOSTOR	Identity thief, e.g.
IMPOSTOR	Phony
IMPOSTOR	Charlatan.
IMPOSTOR	Poseur.
IMPOSTOR	Wolf in sheep's clothing, e.g.
IMPOSTOR	Human phony

Crossword

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