Noun: A face-hugger from Aliens or Aliens vs Predators that has an erect penis instead of a egg depositer on its underside.
Prey 1:"AAAAH FACEMONGER RUN AWAY"
Prey 2:"Well atleast it wont get you pregnant with aliens"
A "playful" offensive term similar to "Jerkface". Often used against someone in a derogatory manner. This word can be easily adapted to an individual's arsenal of "FACE" insults.
Person 1: "These cats are bothering me!"
Person 2: "Your FACE is bothering me!"
Person 1: "Damn it Person 1 you're such a FACEMONGER"