Dictionary/口径こうけいKoukei口径 (Koukei) is a Japanese noun meaning “aperture, bore, calibre, caliber”.Meaningsnounaperture; bore; calibre; caliberKanji in 口径口mouth径diameterRelated words道road口mouth悔しいfrustrated (over a failure, humiliation or injustice)一口mouthful口座account (e.g. bank)水口spout手口modus operandi悪口(verbal) abuse悪口(verbal) abuse入り口entrance出口exit口出しmeddling (in)