1.To become slack; to be made less tense, firm, or rigid; to decrease in tension; as, a wet cord slackens in dry weather.
2.To be remiss or backward; to be negligent.
3.To lose cohesion or solidity by a chemical combination with water; to slake; as, lime slacks.
4.To abate; to become less violent. "Whence these raging fires Will slacken, if his breath stir not their flames."
5.To lose rapidity; to become more slow; as, a current of water slackens.
6.To languish; to fail; to flag.
7.To end; to cease; to desist; to slake. (Obs.) "That through your death your lineage should slack." "They will not of that firste purpose slack."
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