apophysis

Noun

apophysis (plural apophyses)

1. A natural outgrowth, swelling or enlargement, usually of an organism; a protuberance on a bone.
   • Every bone in the real duck had its representative in the automaton, and its wings were anatomically exact. Every cavity, apophysis, and curvature was imitated, and each bone executed its proper movements.1836, E. A. Poe, Maelzel's Chess-Player
   • In the male each palpal tibia shows a long narrow apophysis on the outerside.1913, A. Randell Jackson, “On the British Spiders of the Genus Microneta”, in Transactions of the Natural History Society of Northumberland, page 128
2. The external part of a cone scale.
3. A branch of a dike or vein.
   • Minor palingenetic magmas probably were generated at this time and intruded the mantling rocks in the form of small sills and apophyses; …1980, U.S. Government Printing Office, Geological Survey Professional Paper, Volume 1119