actinotrichium

noun ac·ti·no·trich·i·um \ ¦ak-tə-(ˌ)nō-ˈtri-kē-əm \
variants: or less commonly actinotrich \ak-ˈti-nə-ˌtrik\

Definition of actinotrichium

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

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Origin and Etymology of actinotrichium

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


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