fruity,
From The Oxford Companion to Beer
having the flavor, aroma, or character of fruit. When used in association with beer, fruity is usually a synonym for estery.
Some hop aromatics may also be perceived as fruitlike and are usually reminiscent of citrus fruit. The technique of dry hopping is particularly effective at imparting these compounds to beer. Fruity hop aromatic compounds include limonene (citrus peel), linalool (floral, citrus), and citral (lemon, lime). The aroma of the New Zealand hop variety Nelson Sauvin is reminiscent of passion fruit and gooseberries. Fermentation character and hop character often combine to create complex fruitlike impressions. These will sometimes strike the palate as a form of sweetness, even when little residual sugar is actually present.
Finally, some beers contain actual fruit, usually as a flavoring infusion, although juices may also be used.
When fruity flavors are created by fermentations, restraint is usually best. A beer that seems boldly fruity at first often becomes “perfumey” as it warms, unbalancing the palate and decreasing drinkability. For ale brewers, controlling fermentation to produce the correct balance of fruit character in beer is an important part of the brewer’s art form.
This definition is from The Oxford Companion to Beer, edited by Garrett Oliver. © Oxford University Press 2012.