adjective (a)

• having or exhibiting a single clearly defined meaning(adj.all)

  Example:
  As a horror, apartheid...is absolutely unambiguous.
  

  Antonym:
  ambiguous
  

  source: wordnet30
• admitting of no doubt or misunderstanding; having only one meaning or interpretation and leading to only one conclusion(adj.all)

  Synonym:
  unequivocal, univocal
  Antonym:
  ambiguous, equivocal
  

  source: wordnet30