Hunter eyes are particularly attractive eyes for men. They are the combination of eyes that are darkly colored, vertically narrow, deeply set, hooded, have a positive canthal tilt and an interpupil distance (IPD) within normal range. The hoodedness comes from a protruding brow ridge and fat tissue above the eyes. Hunter eyes are a sexually dimorphic trait. Men exposed to more prenatal androgens have smaller, less neoteneous eyeballs. The female opposite to hunter eyes are roundish, cute, i.e. neotenous eyes that signal harmlessness.
A male with a very bad eye area may be an eyecel.
Deep-set hunter eyes may be an adaptation for combat, hunting and male intrasexual competition, protecting the eyes from fists, claws, sticks etc. and, by extension, may serve the mere intimidation of other males, as was suggested for beards and deep voice. Scientifically, it is an open question to which extent hunter eyes are attractive to women and/or intimidating to other men.
Dark colored eyeballs are also perceived as masculine. A man can have small, dark colored eyeballs but not have developed bones around the eyes and still technically qualify as having hunter eyes. Actor Bruce Campbell has eyes like those.
Color and limbal ring
A study concluded that blue eyes are objectively attractive, as per the stereotype. This is related to the fact that with blue eyes during the day the pupil is most clearly visible. Also, a study concluded that color blue eyes does not increase trust physiognomy.
2 studies show that darker and larger limbal rings around the eyes are more attractive. The study showed women actually, have a revulsion toward faces that lack limbal rings! Especially in a short term mating context. Limbal ring thickness fades with age.