achromaticity

US: (ak′rō mə tis′i tē, ā′krō-)

WordReference Random House Unabridged Dictionary of American English © 2025

ach•ro•ma•tic•i•ty  (ak′rō mə tis′i tē, ā′krō-), n. [Optics.]

1. Optics achromatism.

• achromatic + -ity 1835–45

WordReference Random House Unabridged Dictionary of American English © 2025

ach•ro•mat•ic  (ak′rə mat′ik, ā′krə-), adj. 

1. Optics
   • free from color.
   • able to emit, transmit, or receive light without separating it into colors.
2. Laboratory [Biol.] (of a cell structure) difficult to stain.
3. Music and Dance without accidentals or changes in key.

• a-⁶ + chromatic 1760–70

ach′ro•mat′i•cal•ly, adv. 

Collins Concise English Dictionary © HarperCollins Publishers::

achromatic / ˌækrəˈmætɪk/ adjective

1. without colour
2. capable of reflecting or refracting light without chromatic aberration
3. involving no sharps or flats
4. another word for diatonic

ˌachroˈmatically adverb

achromatism / əˈkrəʊməˌtɪzəm/, achromaticity / əˌkrəʊməˈtɪsɪtɪ/ noun