Answer: stenopaic

AnswerCrossword Clue
STENOPAICHaving a narrow slit
stenopaicpertaining to or containing a narrow slit or minute opening
stenopaicof spectacles, optical instruments, etc., having a narrow slit or aperture; designating such a slit also STENOPAEIC
stenopaicdevice, as of wood, metal, or cardboard, with a narrow horizontal slit, worn over the eyes for protection against bright sunlight