circular opening

Related

holeAbsence in matter
apertureAdjustable optical inlet
ringClosed curve shape
orificeBodily passage entrance
portalImposing entrance or gate

pupil · iris · lens · eyelet · porthole · manhole · drain · vent · socket · loop · halo · disc · rim · hoop · tunnel · mouth · void · grommet

Opposites

shape geometry

circular openingslit

Narrow elongated opening

slot · crack · fissure · gash

openness/closure

circular openingcap

Covering for top

plug · stopper · patch · solid surface · closure

structural presence

circular openingsolid surface

Tangible, unyielding plane

Familiarity: Top 2,000,000