‘退潮’ literally means ‘to retreat + tide’ and refers to the natural phenomenon when seawater recedes from the shore as the tide goes out. The character 退 (tuì) means ‘to withdraw, recede, or retreat’, while 潮 (cháo) means ‘tide’ or ‘tidal current’. Together, they form a compound noun describing the ebb phase of the tidal cycle — the opposite of 涨潮 (zhǎng cháo, ‘tide coming in’). This term is commonly used in coastal geography, marine ecology, weather reporting, and daily life near the sea.

It often appears in contexts involving beach safety, fishing schedules, intertidal zone exploration, or environmental observation. Unlike verbs like ‘to ebb’, ‘退潮’ functions primarily as a noun in Chinese — for example, you say ‘退潮了’ (the tide has gone out), not ‘退潮’ as a standalone verb. It can also be used metaphorically in formal writing to describe a decline or withdrawal of influence, though this is rare in everyday speech.