triophthalmos

tri·oph·thal·mos

(trī'of-thal'mos),
Conjoined twins with union in the facial region such that there is a common eye on the joined sides; a variety of opodidymus. See: conjoined twins.
[tri- + G. ophthalmos, eye]

triophthalmos

(trī″ŏf-thăl′mōs) [″ + ophthalmos, eye]
A deformed fetus with three eyes.