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cinereous

American  
[si-neer-ee-uhs] / sɪˈnɪər i əs /
Also cineritious

adjective

  1. in the state of or reduced to ashes.

    cinereous bodies.

  2. resembling ashes.

  3. ashen; ash-colored; grayish.

    a cinereous bird.


cinereous British  
/ ˌsɪnəˈrɪʃəs, sɪˈnɪərɪəs /

adjective

  1. of a greyish colour

  2. resembling or consisting of ashes

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of cinereous

1655–65; < Latin cinereus, equivalent to ciner- (stem of cinis ) ashes + -eus -eous