opening; hole; gap; orifice
私たちはそのまま洞窟の口にボートで突っ込んで行きました。
We plunged into the cave opening on our boat and continued on.
mouth (of a bottle); spout; nozzle; mouthpiece
ペットボトルの飲み口
The mouth of a plastic bottle
gate; door; entrance; exit
入り口はどこですか?
Where's the entrance?
speaking; speech; talk (i.e. gossip)
恐怖で彼は口がきけなかった。
Fear robbed him of speech.