noun
A narrow stone structure built into the sea to break waves and facilitate loading/unloading of ships. Often smaller than a 防波堤.
See also: 防波堤
港の入り口に波止が築かれている。
A breakwater has been built at the entrance of the harbor.
漁師たちは波止から船に荷物を積み込んだ。
The fishermen loaded the cargo onto the boat from the mole.
防波堤 is a larger, more general breakwater or seawall, while 波止 is a narrower structure often used for loading goods.
Compound of 波 (wave) and 止 (stop), literally 'wave stopper'. The alternate spelling 波戸 uses 戸 (door/gate), possibly suggesting a gate-like structure against waves.