御猪口[ochoko] small cup
片口鰯[katakuchiiwashi] Japanese anchovy (Engraulis japonica)
白口[shiroguchi] white croaker (Pennahia argentata)
悪たれ口[akutareguchi] abuse
悪口雑言[akkouzougon] all kinds of malicious gossip

異口同音[ikudouon] in concert
異口同音に[ikudouonni] in one voice
ひと口[hitokuchi] mouthful
一口商い[hitokuchiakinai] an immediate definite deal
一口同音[ikkudouon] reading in unison

急度[kitto] surely
オリエント急行[orientokyuukou] Orient express
応急[oukyuu] emergency
応急攻撃[oukyuukougeki] hasty attack
応急渡河[oukyuutoka] hasty crossing

火急[kakyuu] emergency
緩急[kankyuu] pace
危急[kikyuu] emergency
危急存亡[kikyuusonbou] life-and-death matter

急須[kyuusu] small teapot
急須の口[kyuusunokuchi] spout of a teapot
恵比須[webisu] Ebisu (god of fishing and commerce)
須臾[shuyu] little while
必須[hissu] indispensable

必須科目[hissukamoku] required subjects
須要[shuyou] absolutely necessary
白長須鯨[shironagasukujira] blue whale (Balaenoptera musculus)
必須条件[hissujouken] essential condition
長須鯨[nagasukujira] fin whale