metopagus

me·top·a·gus

(me-top'ă-gŭs),
Conjoined twins united at the forehead. See: conjoined twins.
[G. metōpon, forehead, + pagos, something fixed]

metopagus

(mĕ-tŏp′ă-gŭs) [Gr. metopon, forehead, + pagos, thing fixed]
Conjoined twins united at the forehead.