From Arabic qolqotar (qolqotar).


colcothar (countable and uncountable, plural colcothars)

  1. (organic chemistry, obsolete) Polishing rouge; a reddish-brown oxide of iron, used in polishing glass, and also as a pigment; crocus Martis.

Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.