A general term for eye deviation is "strabismus". In looking at etymology in dictionary, I was reminded of the historian and geographer Strabo. I found many sites about him, but not surprisingly no statement as to whether his name was or was not derived from deviation of one eye.
Cognomen is the only word I can think of for name given because of a physical characteristic. Can any of you think of a better word? Cicero is an example, based on head of his branch having a prominent wart on his nose, or something like that. Survives in "chick peas". Wait till CK sees this.