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

介添え[kaizoe] helper
寄添う[yorisou] to get close
後添い[nochizoi] one's second wife
食品添加物[shokuhintenkabutsu] food additive
申し添える[moushisoeru] to add to what has been said

添う[sou] to meet (one's expectations, etc.)
添加[tenka] addition
添加剤[tenkazai] addition agent
添加物[tenkabutsu] addition
添削[tensaku] correction