to become gradually less or smaller

waste away; taper off

to become less severe or cruel (especially by agreeing to something after refusing)

die down; let up

(of flood water) to sink to a lower or to the usual level

die down; decrease

(to cause something) to become gradually narrower towards one end; a length of string with a covering of wax, burnt to give a light

decrease

to become less or weaker; (of the moon) to show a decreasing bright area after full moon

diminish, lessen