口こう径けいTop 15000MeaningsNoun1. aperture; bore; calibre; caliberKanji used口mouth径diameterPitch accentこうけいUsed in vocabulary小しょう口こう径けいsmall calibre; small caliberNoun口こう径けい食しょくvignettingNoun口こう径けい比ひaperture ratio (inverse of the f-number); relative apertureNoun