pigment
noun /ˈpɪɡmənt/
  /ˈpɪɡmənt/
[uncountable, countable]- a substance that exists naturally in people, animals and plants and gives their skin, leaves, etc. a particular colour色素 - Haemoglobin is the red pigment found in blood.血红蛋白是血液中发现的红色色素。 
 
- Haemoglobin is the red pigment found in blood.
- a coloured powder that is mixed with a liquid to produce paint, etc.颜料 - The wool is coloured using only natural pigment dyes.羊毛只用天然色素染色。 
 
- The wool is coloured using only natural pigment dyes.
词源Middle English, from Latin pigmentum, from pingere ‘to paint’