御三時[osanji] three-o'clock snack
三鞭酒[shanpen] champagne
球面三角法[kyuumensankakuhou] spherical trigonometry
胸三寸[munesanzun] heart
元三[ganzan] New Year's period (January 1st to 3rd)

五十三次[gojuusantsugi] the 53 Toukaidou stages
向こう三軒[mukousangen] one's next three neighbors
降三世明王[gouzanzemyouou] Trailokyavijaya Vidya-raja
再三[saisan] again and again
再三再四[saisansaishi] repeatedly

雨子[amago] land-locked variety of red-spotted masu trout (Oncorhynchus masou ishikawae)
御菓子[okashi] confections
お子さん[okosan] (someone else's) child
お子様[okosama] child (someone else's)
山梔子[kuchinashi] Cape jasmine (Gardenia jasminoides)

させ子[saseko] whore
梃子摺る[tekozuru] to have much trouble
螺子回し[nejimawashi] screwdriver
硝子[garasu] glass
獅子女[sufinkusu] sphinx

手枷[tegase] handcuffs
足枷[ashikase] fetters
首枷[kubikase] pillory
連枷[karazao] flail (for threshing grain)

手枷足枷[tekaseashikase] manacles
口枷[kuchikase] (mouth) gag
枷蚯蚓[kasemimizu] Epimenia verrucosa (mollusc)
子は三界の首枷[kohasangainokubikase] A child is an everlasting responsibility to parents

医界[ikai] medical world
医学界[igakukai] medical world
黄金世界[ougonsekai] utopia
下界[gekai] this world
花柳界[karyuukai] red-light district

界隈[kaiwai] neighborhood
界面[kaimen] interface
各界[kakkai] each field
学界[gakkai] academic or scientific world
官界[kankai] bureaucracy

一首[isshu] tanka
鎌首[kamakubi] sickle-shaped neck (e.g. snake, praying mantis)
丸首[marukubi] round-necked (T-shirt)
偽首[nisekubi] falsified severed head
カリ首[karikubi] (something resembling a) goose's neck

がん首[gankubi] head of a pipe, incl. the bowl and stem attachment
機首[kishu] nose (of plane)
襟首[erikubi] nape of neck
元首[genshu] ruler
絞首刑[koushukei] death by hanging