Definition of siennas:
(n) :
(countable and uncountable) A pigment with a reddish-brown colour.
(n) :
(countable and uncountable) A light reddish-brown colour.
(adj) :
having a reddish-brown colour.
(n) :
(countable) A form of clay containing iron and manganese.
(n) :
A female given name from English of modern usage from the sienna colour.