A type of extra terrestrial being (alien). Usually the most common amongst alleged abductees. Also the type most commonly connoted with the Rosswell, New Mexico crash site.
Some believe Greys are of the same species of alien as Reptilian. This is debatable.
A slang word used to describe a person of color who is either not proud of his/her heritage or does not "act black". Or a black person that "acts white". Could also be spelled Gray.