A reptilian animal: a reptile.
A reptilian person, especially (racial slur) a Jew.
A reptilian alien, especially (often capitalized) of a shapeshifting race purported to secretly control the world.
Of or relating to the members of the class Reptilia.
Reptilelike.
Unthinking, low, base, contemptible.
Cold-blooded, treacherous, unavoidably selfish and hostile.