lessen vs slack up

Other hyponyms of lessen include suppress, mitigate, pare, pare down, circumscribe, confine to, limit, boil down, concentrate, reduce, reduce, shrink, abbreviate, abridge, contract, cut, foreshorten, reduce, shorten, abate, slack, slake, lour, lower, turn down, de-escalate, step down, weaken, minimise, minimize, bring down, cut, cut back, cut down, reduce, trim, trim back, trim down, cut, relax, slack, slacken, belittle, diminish.