炯々[keikei] glaring (e.g. eyes)
炯眼[keigan] penetrating eyes

眼光炯炯[gankoukeikei] having piercing eyes
炯然[keizen] shining

一眼[ichigan] one eye
一眼レフ[ichiganrefu] single-lens reflex camera
一隻眼[issekigan] sharp eye
遠眼[engan] farsightedness
遠眼鏡[toomegane] spectacles for far-sightedness

凹眼[ougan] cavernous eyes
凹眼鏡[ougankyou] concave glasses
開眼[kaigan] enlightenment
眼下[ganka] under one's eyes
眼科[ganka] ophthalmology