The Collaborative International Dictionary
Ectostosis
Ectostosis \Ec`tos*to"sis\, n. [NL. See Ect-, and Ostosis.] (Physiol.) A process of bone formation in which ossification takes place in the perichondrium and either surrounds or gradually replaces the cartilage.
Wiktionary
ectostosis
n. (context physiology English) A process of bone formation in which ossification takes place in the perichondrium and either surrounds or gradually replaces the cartilage.