Sour \Sour\, a. [Compar. Sourer; superl. Sourest.]

[OE. sour, sur, AS. s?r; akin to D. zuur, G. sauer, OHG. s?r, Icel. s?rr, Sw. sur, Dan. suur, Lith. suras salt, Russ. surovui harsh, rough. Cf. Sorrel, the plant.]

1. Having an acid or sharp, biting taste, like vinegar, and the juices of most unripe fruits; acid; tart.

All sour things, as vinegar, provoke appetite. --Bacon.

2. Changed, as by keeping, so as to be acid, rancid, or musty, turned.

3. Disagreeable; unpleasant; hence; cross; crabbed; peevish; morose; as, a man of a sour temper; a sour reply. ``A sour countenance.'' --Swift.

He was a scholar . . . Lofty and sour to them that loved him not, But to those men that sought him sweet as summer. --Shak.

4. Afflictive; painful. ``Sour adversity.'' --Shak.

5. Cold and unproductive; as, sour land; a sour marsh.

Sour dock (Bot.), sorrel.

Sour gourd (Bot.), the gourdlike fruit Adansonia Gregorii, and A. digitata; also, either of the trees bearing this fruit. See Adansonia.

Sour grapes. See under Grape.

Sour gum (Bot.) See Turelo.

Sour plum (Bot.), the edible acid fruit of an Australian tree (Owenia venosa); also, the tree itself, which furnished a hard reddish wood used by wheelwrights.

Syn: Acid; sharp; tart; acetous; acetose; harsh; acrimonious; crabbed; currish; peevish.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Tupelo \Tu"pe*lo\, n. [Tupelo, or tupebo, the native American Indian name.]

(Bot.) A North American tree (Nyssa multiflora) of the Dogwood family, having brilliant, glossy foliage and acid red berries. The wood is crossgrained and very difficult to split. Called also black gum, sour gum, and pepperidge.

Largo tupelo, or Tupelo gum (Bot.), an American tree (Nyssa uniflora) with softer wood than the tupelo.

Sour tupelo (Bot.), the Ogeechee lime.

Source: Webster's Revised Unabridged Dictionary (1913)