What is Ebb ?
Ebb is (noun) (of tides) going down If we leave at 3.00 p.m. the tide will be on the ebb. Antonym flow to be at a low ebb to be in a bad state After his interview, his morale was at a low ebb. The manager asked them to try harder, just when their energy was at its lowest ebb. (verb) 1. (of tides) to go down Boats at anchor swing round to point upstream when the tide starts to ebb. 2. to ebb away to become weaker gradually He couldn’t hold on to the life-raft any longer; his strength was ebbing away.
source: Easier English, Student Dictionary Upper Intermediate Level