n. A lustrous yellow, green, or black mineral, Ca2(Al, Fe)3(SiO4)3OH, commonly found in metamorphic rock. [French épidote, from Greek epididonai, to give in addition, increase (from the greater length of its crystals compared with those of related minerals) : epi-, epi- + didonai, to give; see dō- in the Appendix of Indo-European roots.] ep′i·dotic (-dŏtĭk) adj. |
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.