n. & v.
n. 1 the movement of the tide out to sea (also attrib. : ebb tide). 2 the process of draining away of flood-water etc.
v.intr. (often foll. by away) 1 (of tidewater) flow out to sea; recede; drain away. 2 decline; run low (his life was ebbing away). at a low ebb in a poor condition or state of decline. ebb and flow a continuing process of decline and upturn in circumstances. on the ebb in decline.
[ OE ebba, ebbian ]