A type of alien in science fiction that is portrayed by a man or woman wearing prosthetic makeup. Usually, these aliens look almost completely human, with the exception of certain facial features, such as enlarged noses, horns, ridged brows, etc. These are common in sci-fi tv shows that have low budgets, but they can also be a common sight in higher budget franchises such as Star Wars (the twi'lek, for example). This term can also apply to aliens from video games, a prime example being the Asari from Mass Effect.
Guy 1: The Asari from Mass Effect are such rubber forehead aliens.

Guy 2: That's nothing! What about Ka D'argo from Farscape?
by BatteryMaster June 3, 2016
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