burble vs slack

burble

noun
  • A bubbling, gurgling sound, as of a creek. 

  • The turbulent boundary layer about a moving streamlined body. 

  • Trouble; disorder. 

  • A gush of rapid speech. 

verb
  • To babble; to speak in an excited rush. 

  • To trouble or confuse. 

  • To bubble; to gurgle. 

slack

noun
  • A tidal marsh or shallow that periodically fills and drains. 

  • Unconditional listening attention given by client to patient. 

  • A temporary speed restriction where track maintenance or engineering work is being carried out at a particular place. 

  • The part of anything that hangs loose, having no strain upon it. 

  • Small coal; coal dust. 

  • A valley, or small, shallow dell. 

adj
  • Moderately warm. 

  • Vulgar; sexually explicit, especially in dancehall music. 

  • Not active or busy, successful, or violent. 

  • Excess; surplus to requirements. 

  • Lax; not tense; not firmly extended. 

  • Lacking diligence or care; not earnest or eager. 

  • Lax. 

  • Moderate in speed. 

  • Weak; not holding fast. 

adv
  • Slackly. 

verb
  • To slacken. 

  • To lose cohesion or solidity by a chemical combination with water; to slake. 

How often have the words burble and slack occurred in a corpus of books? (source: Google Ngram Viewer )