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verb slack·en \ˈsla-kən\

Simple Definition of slacken

  • : to become slower or less active : to slow down

  • : to make (something) slower or less active

  • : to become less tight or to make (something) less tight

Source: Merriam-Webster's Learner's Dictionary

Full Definition of slacken



play \ˈsla-kən-iŋ\
  1. transitive verb
  2. 1 :  to make less active :  slow up <slacken speed at a crossing>

  3. 2 :  to make slack (as by lessening tension or firmness) <slacken sail>

  4. intransitive verb
  5. 1 :  to become slack or slow or negligent :  slow down

  6. 2 :  to become less active :  slack

Examples of slacken in a sentence

  1. Sales show no sign of slackening.

  2. As he began to relax, his grip on the steering wheel slackened.

  3. The captain ordered us to slacken the sails.

14th Century

First Known Use of slacken

14th century

Synonym Discussion of slacken

delay, retard, slow, slacken, detain mean to cause to be late or behind in movement or progress. delay implies a holding back, usually by interference, from completion or arrival <bad weather delayed our arrival>. retard suggests reduction of speed without actual stopping <language barriers retarded their progress>. slow and slacken also imply a reduction of speed, slow often suggesting deliberate intention <medication slowed the patient's heart rate>, slacken an easing up or relaxing of power or effort <on hot days runners slacken their pace>. detain implies a holding back beyond a reasonable or appointed time <unexpected business had detained her>.

delay, procrastinate, lag, loiter, dawdle, dally mean to move or act slowly so as to fall behind. delay usually implies a putting off (as a beginning or departure) <we cannot delay any longer>. procrastinate implies blameworthy delay especially through laziness or apathy <procrastinates about making decisions>. lag implies failure to maintain a speed set by others <lagging behind in technology>. loiter and dawdle imply delay while in progress, especially in walking, but dawdle more clearly suggests an aimless wasting of time <loitered at several store windows> <children dawdling on their way home from school>. dally suggests delay through trifling or vacillation when promptness is necessary <stop dallying and get to work>.

SLACKEN Defined for Kids


verb slack·en \ˈsla-kən\

Definition of slacken for Students



  1. 1 :  to make slower or less energetic <The wind slackened.>

  2. 2 :  to make less tight or firm <She slackened the reins.>

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