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

碓氷峠[usuitouge] Usui Pass
月下氷人[gekkahyoujin] go-between
砕氷船[saihyousen] ice breaker
削氷機[sakuhyouki] ice-shaving machine

樹氷[juhyou] frost covered trees
製氷[seihyou] ice making
そう氷[souhyou] pack ice
欠氷[kakigoori] shaved ice (usually served with flavored simple syrup)