calcar

plural calcars

1. A small oven or furnace, used for the calcination of sand and potash, and converting them into frit.

plural calcars · plural calcaria

1. anatomyA spur-like projection.

   ... calcars. When the tail is long (equal to or longer than the length of the hind legs) and calcars are present [...] calcar is absent in all known specimens[…]

   2023 November 21, Danilo Russo, Brock Fenton, A Natural History of Bat Foraging: Evolution, Physiology, Ecology, Behavior, and Conservation, Elsevier, →ISBN, page 19

   2 more examples

   ... a calcar, the apical spine of the inner series must in many of the species be also considered as such, since the appearance of both, and their position as regards the calcaria, are precisely similar. This apical spine of the inner[…]

   1913, David Sharp, Fauna Hawaiiensis: Being the Land-fauna of the Hawaiian Islands, page 23

   ... The calcaria are frequently specified in the taxonomy of insects and are [...] a calcar is known as a strigilis. [...] A calcar and sometimes some of the adjacent setae are used for closing the[…]

   1923, Alexander Dyer MacGillivray, External Insect-anatomy: A Guide to the Study of Insect Anatomy and an Introduction to Systematic Entomology, page 245