ac·​tin·​o·​lite ak-ˈti-nə-ˌlīt How to pronounce actinolite (audio)
: a bright green or grayish-green mineral of the amphibole group that is a silicate of calcium, magnesium, and iron occurring in fibrous, radiate, or columnar forms

Word History


actino- + -lite; translation of German Strahlstein, Strahlschörl (earlier New Latin actinotus in the terminology of the naturalist J. F. Gmelin)

First Known Use

1794, in the meaning defined above

Time Traveler
The first known use of actinolite was in 1794

Dictionary Entries Near actinolite

Cite this Entry

“Actinolite.” Dictionary, Merriam-Webster, Accessed 18 May. 2024.

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