Short definition
Scents in wine that come directly from the grape variety itself, as opposed to winemaking or aging.
Aroma refers specifically to smells that originate from the grape — the blackcurrant of Cabernet, the lychee of Gewürztraminer, the green pepper of under-ripe Carménère. These are called primary aromas. As wine ages, these fresh grape-driven scents fade and give way to bouquet, which comes from chemical changes during aging.