Ombre \Om"bre\, n. [F., of uncertain origin.]

(Zo["o]l.) A large Mediterranean food fish (Umbrina cirrhosa): -- called also umbra, and umbrine.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Penumbra \Pe*num"bra\, n. [NL., fr. L. paene almost + umbra shade.]

1. An incomplete or partial shadow.

2. (Astron.) The shadow cast, in an eclipse, where the light is partly, but not wholly, cut off by the intervening body; the space of partial illumination between the umbra, or perfect shadow, on all sides, and the full light. --Sir I. Newton.

Note: The faint shade surrounding the dark central portion of a solar spot is also called the penumbra, and sometimes umbra.

3. (Paint.) The part of a picture where the shade imperceptibly blends with the light.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Umbra \Um"bra\, n.; pl. Umbr[ae]. [L., a shadow.]

1. (Astron.)
   (a) The conical shadow projected from a planet or satellite, on the side opposite to the sun, within which a spectator could see no portion of the sun's disk; -- used in contradistinction from penumbra. See Penumbra.
   (b) The central dark portion, or nucleus, of a sun spot.
   (c) The fainter part of a sun spot; -- now more commonly called penumbra.

2. (Zo["o]l.) Any one of several species of sci[ae]noid food fishes of the genus Umbrina, especially the Mediterranean species (U. cirrhosa), which is highly esteemed as a market fish; -- called also ombre, and umbrine.

Umbra tree (Bot.), a tree (Phytolacca diocia) of the same genus as pokeweed. It is native of South America, but is now grown in southern Europe. It has large dark leaves, and a somber aspect. The juice of its berries is used for coloring wine. --J. Smith (Dict. Econ. Plants).

Source: Webster's Revised Unabridged Dictionary (1913)