[syn: laxness, laxity, remissness, slackness]
The Collaborative International Dictionary of English v.0.48:
Slackness \Slack"ness\, n.
   The quality or state of being slack.
   [1913 Webster]
WordNet (r) 3.0 (2006):
slackness
    n 1: weakness characterized by a lack of vitality or energy
         [syn: inanition, lassitude, lethargy, slackness]
    2: the quality of being loose (not taut); "he hadn't counted on
       the slackness of the rope" [syn: slack, slackness]
    3: the quality of being lax and neglectful [syn: laxness,
       laxity, remissness, slackness]