adverb (r)

• with low volume(adv.all)

  Example:
  She spoke quietly to the child.
  

  Synonym:
  softly
  Antonym:
  aloud, loud, loudly
  

  source: wordnet30
• with little or no sound(adv.all)

  Example:
  The class was listening quietly and intently.
  She was crying quietly.
  

  Antonym:
  noisily
  

  source: wordnet30
• with little or no activity or no agitation (`quiet' is a nonstandard variant for `quietly')(adv.all)

  Example:
  Her hands rested quietly in her lap.
  The rock star was quietly led out the back door.
  

  Synonym:
  quiet
  Antonym:
  unquietly
  

  source: wordnet30
• in a restful manner(adv.all)

  Synonym:
  restfully
  

  source: wordnet30
• In a quiet state or manner; without motion; in a state of rest; as, to lie or sit quietly.(adverb)

  source: webster1913