noun (n)

• weakness characterized by a lack of vitality or energy

  kelemahan ditandai oleh kekurangan semangat atau energi

  Synonym:
  inanition, lassitude, lethargy
  

  source: wordnet30
• the quality of being loose (not taut)

  kualiti menjadi longgar (kendur)

  Example:
  He hadn't counted on the slackness of the rope.
  

  Synonym:
  slack
  

  source: wordnet30
• the quality of being lax and neglectful

  kualiti menjadi lax dan lalai

  Synonym:
  laxity, laxness, remissness
  

  source: wordnet30
• The quality or state of being slack.

  kualiti atau keadaan menjadi kendur.

  source: webster1913