variants or less commonly actinotrich
plural actinotrichia
also actinotrichs
: 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


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.” Dictionary, Merriam-Webster, Accessed 27 May. 2024.

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