Match the smells to the molecule:<p><pre><code>  farts          methyl mercaptan (thiol + methyl)
  durian&#x2F;onion   ethyl mercaptan (thiol + ethyl)
  skunk          butyl mercaptan (thiol + butyl)
  coffee         furfuryl mercaptan (furan + 2-methanethiol)
  grapefruit     grapefruit mercaptan (cyclohexene + 1-methyl + 4R-isopropyl-2-thiol)
  lilac          alpha-terpineol (cyclohexene + 1-methyl + 4-isopropyl-2-ol)
  almond&#x2F;cherry  benzaldehyde (phenyl + formyl)
  anise          anisaldehyde (phenyl + 1-formyl + 4-methoxy)
  cinnamon       cinnamadehyde (phenyl + acrolein)
  tar            cresol (phenyl + 1-hydroxy + (2 or 3 or 4)-methyl)
  smoke          guaiacol (phenyl + 1-hydroxy + 2-methoxy)
  vanilla        vanillin (phenyl + 1-hydroxy + 2-methoxy + 4-formyl)
  clove          eugenol (phenyl + 1-hydroxy + 2-methoxy + 4-allyl)
  oregano        carvacrol (phenyl + 1-hydroxy + 2-methyl + 5-isopropyl)
  thyme          thymol (phenyl + 1-hydroxy + 2-isopropyl + 5-methyl)
  mint           menthol (cyclohexanyl + 1R-hydroxy + 2S-isopropyl + 5R-methyl)
  caraway        [S+]-carvone (1-cyclohex-2-enone + 2-methyl + 5S-isopropenyl)
  spearmint      [R-]-carvone (1-cyclohex-2-enone + 2-methyl + 5R-isopropenyl)
  pine           [S-]-limonene (cyclohexene + 1-methyl + 4S-isopropenyl)
  orange         [R+]-limonene (cyclohexene + 1-methyl + 4R-isopropenyl)
  fish           trimethylamine
  cabbage&#x2F;ocean  dimethyl sulfide
  butter         diacetyl + acetoin
  vomit          butyric acid
  pineapple      methyl butyrate
  orange         ethyl butyrate
  strawberry     propyl butyrate, butyl butyrate
  pear&#x2F;apricot   pentyl butyrate
  glue           methyl acetate
  pear           ethyl acetate
  apple&#x2F;banana   butyl acetate, amyl acetate
  vinegar        acetic acid
  goat cheese    capric acid, caprylic acids
  popcorn        6-acetyl-1,2,3,4-tetrahydro-pyridine
  coconut        gamma-nonalactone
  peach          gamma-undecalactone
  garlic         diallyl disulfide, diallyl trisulfide, diallyl tetrasulfide
</code></pre>
So I&#x27;d say that olfaction primitives probably number at least in the low hundreds.  It seems as though just substituting a single functional group on an aromatic ring or changing the length of a carbon chain can affect human perception of the odor.  Chirality usually matters.  Orientation of the double bonds usually matters.  Most frustratingly, <i>concentration</i> also matters.  Indole smells like jasmine flowers at low concentrations and like poop at higher concentrations.<p>It may well be that we don&#x27;t have dedicated words for smells because the IUPAC chemical naming conventions make them unnecessary.  Also, most people don&#x27;t need them.  Professional aromatists would probably just say the chemical name, or use the perfumery primitives like the plant essential oils or resins, ambergris, civet, castoreum, hyrax, musk, and beeswax.<p>Esters are fruity.  Linear terpenes are grassy or herby.  Cyclic terpenes are woody or flowery.  Substituted aromatics are flowery or herby.  Amines are rotten or fishy.  Thiols just plain stink.<p>Wine snobs can probably just make up whatever words they want to describe their noses and bouquets, because their words don&#x27;t really transmit meaning most of the time, anyway.