If you only learn a handful of shore words, make them these. They are the ones that decide whether a day on the coast goes well or badly.
Spring tide (大潮)
An unusually large tide around new and full moon, when the sun and moon pull together. Water runs higher, lower and faster. It is great for tidepooling and beachcombing, and dangerous for anyone on a low path.
Neap tide (小潮)
A small, gentle tide around the first and last quarter moon, when sun and moon pull at right angles. Less water moves, pools barely empty, and rock routes stay drier.
Flood tide (涨潮) & ebb tide (退潮)
Flood is the tide rising toward high water; ebb is it falling toward low. Most people get caught on a rising flood, not a falling ebb.
Slack water (平潮)
The brief pause at high or low tide when the current stops before it turns. The calmest time for snorkelling and boating; it rarely lasts long.
Rip current (离岸流)
A strong narrow current flowing straight out through the surf. If caught in one, don't fight it — swim parallel to the shore, then drift in.
Tide pool (潮池)
The shallow water trapped on the rocky shore when the tide goes out. Its creatures depend on you looking, not taking.
Tidal range (潮差)
The vertical difference between high water and low water. Bigger range = more beach exposed at low tide and faster-moving water.
Datum (基准面)
The reference level (like chart datum) from which tide heights are measured. Heights on a tide table are not arbitrary — they start from this line.
Tidal bore (涌潮)
A wall of water that rushes up some narrow estuaries against the river current on a rising tide. Spectacular, and not to be underestimated.
Strandline (潮线)
The line of seaweed, shells and flotsam the tide leaves on the beach — both the beachcomber's map and your warning of where high water reached.