The Collaborative International Dictionary of English v.0.48:
Umber \Um"ber\, n. [F. ombre ocherous ore of iron, terre
d'ombre, It. terra d'ombra, literally, earth of shadow or
shade, L. umbra shadow, shade. Cf. Umber, 3 & 4,
1. (Paint.) A brown or reddish pigment used in both oil and
water colors, obtained from certain natural clays
variously colored by the oxides of iron and manganese. It
is commonly heated or burned before being used, and is
then called burnt umber; when not heated, it is called
raw umber. See Burnt umber, below.
2. An umbrere. [Obs.]
3. [F. ombre, umbre, L. umbra.] (Zool.) See Grayling, 1.
4. [Cf. NL. scopus umbretta, F. ombrette; probably fr. L.
umbra shade, in allusion to its dark brown color. See
Umber a pigment.] (Zool.) An African wading bird
(Scopus umbretta) allied to the storks and herons. It is
dull dusky brown, and has a large occipital crest. Called
also umbrette, umbre, and umber bird.
Burnt umber (Paint.), a pigment made by burning raw umber,
which is changed by this process from an olive brown to a
bright reddish brown.
Cologne umber, or German umber, a brown pigment obtained
from lignite. See Cologne earth.