at·ra·ment \ˈa.trəmənt\noun (-s) Etymology: Middle English, from Latin atramentum, from (assumed) Latin atrare to make black (from Latin atr-, ater black) + Latin -mentum -ment — more at atrocious 1.obsolete: ink < writing with atrament > 2.: a very dark substance — usually used of liquids < a puff of atrament emitted by the octopus >