Word Study
sienna
CIDE DICTIONARY
sienna, n. [It. terra di Siena, fr. Siena in Italy.].
Clay that is colored red or brown by the oxides of iron or manganese, and used as a pigment. It is used either in the raw state or burnt. [1913 Webster]
OXFORD DICTIONARY
sienna, n.
1 a kind of ferruginous earth used as a pigment in paint.
2 its colour of yellowish-brown (raw sienna) or reddish-brown (burnt sienna).
1 a kind of ferruginous earth used as a pigment in paint.
2 its colour of yellowish-brown (raw sienna) or reddish-brown (burnt sienna).
Etymology
It. (terra di) Sienna (earth of) Siena in Tuscany
For further exploring for "sienna" in Webster Dictionary Online