Old English biternys "bitterness, grief;" see bitter + -ness. Figurative sense (of feelings, etc.) is attested earlier than literal sense (of taste), which will surprise no one who reads any [..]

In beer, the bitterness is caused by the tannins and iso-humulones of hops. Bitterness of hops is perceived in the taste. The amount of bitterness in a beer is one of the defining characteristics of a [..]

resentment: a feeling of deep and bitter anger and ill-will a rough and bitter manner bitter: the taste experience when quinine or coffee is taken into the mouth the property of having a harsh unpleas [..]

n. Acridity, as to the taste.

(n) a feeling of deep and bitter anger and ill-will(n) a rough and bitter manner(n) the taste experience when quinine or coffee is taken into the mouth(n) the property of having a harsh unpleasant tas [..]

acerbitas, ruta, amaritudo

in that astringency is felt throughout the mouth, while bitterness is experienced only by the tastebuds of the tongue. Attenuation:

A lingering taste sensation, detected totally in the mouth on the tastebuds of the tongue, and therefore differs from astringency

The perception of a bitter flavor, in beer from iso-alpha-acid in solution (derived from hops). It is measured in International Bitterness Units (IBU).

The bitter substances in beer which are mainly iso-alpha acids.