English edit

Etymology edit

From New Latin, from Ancient Greek ἀκτίς (aktís, ray) + ὀστέον (ostéon, bone).

Noun edit

actinost (plural actinosts)

  1. (ichthyology) A bone at the base of a paired fin (of a fish)
    • 1889, Dr. G. Baur, “On the morphology of ribs and the fate of the actinosts of the median fin in fishes”, in Journal of morphology[1], volume 3:
      The second well-developed actinost is below the vertebra supporting the subcaudal blood-vessels, but that is not so strong proximally as the first; the ribs are not directed downwards, but backwards, and are entirely separated from each other.

Anagrams edit