noun (n)

• acceptance without protest(noun.state)

  source: wordnet30
• agreement with a statement or proposal to do something(noun.communication)

  Example:
  A murmur of acquiescence from the assembly.
  

  Synonym:
  assent
  

  source: wordnet30
• A silent or passive assent or submission, or a submission with apparent content; -- distinguished from avowed consent on the one hand, and on the other, from opposition or open discontent; quiet satisfaction.(noun)

  source: webster1913