aperture
noun
[ ˈapətʃə ]
• an opening, hole, or gap.
• "the bell ropes passed through apertures in the ceiling"
Similar:
opening,
hole,
gap,
space,
slit,
slot,
vent,
passage,
crevice,
chink,
crack,
fissure,
perforation,
breach,
eye,
interstice,
orifice,
foramen,
Origin:
late Middle English: from Latin apertura, from apert- ‘opened’, from aperire ‘to open’.