Of persons: To diminish the intensity of one's efforts; to become less energetic or eager; also, to undergo or manifest a weakening or decrease…

Const. to with infinitive. Obsolete.

= flag, v.1 in various intransitive senses. To become languid or flabby. Of a garment: To fall in folds. Obsolete.

Of persons (or animals): To become less energetic, active, or diligent.

Of persons: To become lax, remiss, or negligent; to grow less energetic or eager.

intransitive. To cease or lessen one's efforts; to rest; to seek or take recreation. Also with in, into, from.

To cease to go on with, or prosecute, in a vigorous and energetic manner; to allow to fall off or decline. Also to slack one's hand(s), to…

intransitive. To become less frequent or assiduous in.

To relax or cease one's efforts, spec. in rowing; also with up; to ease all, to stop rowing (cf. easy, v.).

Similarly with off.

to ease off. intransitive. To take things easily.