noun (n)

• any property detected by the olfactory system(noun.attribute)

  Synonym:
  odor, odour, olfactory property, scent, smell
  

  source: wordnet30
• a distinctive odor that is pleasant(noun.cognition)

  Synonym:
  fragrance, perfume, scent
  

  source: wordnet30
• The quality or principle of plants or other substances which constitutes their fragrance; agreeable odor; as, the aroma of coffee.(noun)

  source: webster1913