"Gubber Tushed is when teeth stand out, and not in order." [R. Holme, "Armoury," 1688].
Every Lover admires his Mistress, though she have ... a nose like a promontory, gubber-tushed, rotten teeth, (etc.). [Robert Burton, "Anatomy of Melancholy," 1621]
Online Etymology Dictionary, © 2010 Douglas Harper