Search Result for "slackening": 
Wordnet 3.0

NOUN (1)

1. an occurrence of control or strength weakening;
- Example: "the relaxation of requirements"
- Example: "the loosening of his grip"
- Example: "the slackening of the wind"
[syn: relaxation, loosening, slackening]

The Collaborative International Dictionary of English v.0.48:

Slack \Slack\, Slacken \Slack"en\, v. i. [imp. & p. p. Slacked, Slackened; p. pr. & vb. n. Slacking, Slackening.] [See Slack, a.] 1. To become slack; to be made less tense, firm, or rigid; to decrease in tension; as, a wet cord slackens in dry weather. [1913 Webster] 2. To be remiss or backward; to be negligent. [1913 Webster] 3. To lose cohesion or solidity by a chemical combination with water; to slake; as, lime slacks. [1913 Webster] 4. To abate; to become less violent. [1913 Webster] Whence these raging fires Will slacken, if his breath stir not their flames. --Milton. [1913 Webster] 5. To lose rapidity; to become more slow; as, a current of water slackens. [1913 Webster] 6. To languish; to fail; to flag. [1913 Webster] 7. To end; to cease; to desist; to slake. [Obs.] [1913 Webster] That through your death your lineage should slack. --Chaucer. [1913 Webster] They will not of that firste purpose slack. --Chaucer. [1913 Webster] Slack
WordNet (r) 3.0 (2006):

slackening n 1: an occurrence of control or strength weakening; "the relaxation of requirements"; "the loosening of his grip"; "the slackening of the wind" [syn: relaxation, loosening, slackening]
Moby Thesaurus II by Grady Ward, 1.0:

74 Moby Thesaurus words for "slackening": abatement, allayment, alleviation, arrest, assuagement, attenuation, attrition, blunting, calming, check, damping, deadening, debilitation, deceleration, delay, demulsion, detention, devitalization, dilution, diminution, drag, dulcification, dulling, ease-off, ease-up, easing, effemination, enervation, enfeeblement, evisceration, exhaustion, extenuation, falling-off, fatigue, flagging, holdup, hushing, inanition, lag, languishment, leniency, lessening, letdown, letup, lightening, loosening, lulling, minus acceleration, mitigation, modulation, mollification, obstruction, pacification, palliation, quietening, quieting, reduction, relaxation, remission, retardation, retardment, setback, slack-up, slowdown, slowing, slowing down, slowup, softening, soothing, subduement, tempering, thinning, tranquilization, weakening