ach·ro·mat·ic (ăk′rə-mătĭk, ā′krə-)
1. Designating color perceived to have zero saturation and therefore no hue, such as neutral grays, white, or black.
2. Refracting light without spectral color separation.
3. Biology Difficult to stain with standard dyes. Used in reference to cells or tissues.
4. Music Having only the diatonic tones of the scale.
[From Greek akhrōmatos : a-, without; see A-1 + khrōma, khrōmat-, color.]
a·chro′ma·tici·ty (-tĭsĭ-tē) n.
a·chroma·tism (ā-krōmə-tĭz′əm) n.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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