ebb suggests the receding of something (such as the tide) that commonly comes and goes.

Idiom ebb and flow (Definition of ebb from the Cambridge Academic Content Dictionary © Cambridge University Press)

a flowing backward or away; decline or decay. the ebb of a once great nation. a point of decline. His fortunes were at a low ebb. to flow back or away, as the water of a tide (flow ). to decline …

In an Earthquake Brace + Bolt (EBB) seismic retrofit, the foundation is "bolted" to the frame of the house, and when there are walls called "cripple walls" in the crawl space under the house, …

Definition of ebb noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

The ebb or the ebb tide is one of the regular periods, usually two per day, when the sea gradually falls to a lower level as the tide moves away from the land. ...the spring ebb tide. We decided …

When something ebbs, it is declining, falling, or flowing away. The best time to look for sea creatures in tidal pools is when the tide is on the ebb — meaning it has receded from the shore.