actinotrichium

noun

ac·​ti·​no·​trich·​i·​um
¦ak-tə-(ˌ)nō-ˈtri-kē-əm
variants or less commonly actinotrich
ak-ˈti-nə-ˌtrik
plural actinotrichia
¦ak-tə-(ˌ)nō-ˈtri-kē-ə
also actinotrichs
ak-ˈti-nə-ˌtriks
: any of the hairy threadlike fibers in the fin fold of an embryo fish which fuse and form the base of the rays

Word History

Etymology

New Latin actinotrichium, from actin- + Greek trich-, thrix hair + New Latin -ium

First Known Use

1885, in the meaning defined above

Time Traveler
The first known use of actinotrichium was in 1885

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Dictionary Entries Near actinotrichium

Cite this Entry

“Actinotrichium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/actinotrichium. Accessed 27 May. 2024.

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