Main Entry: col·la·gen

Pronunciation: \ˈkä-lə-jən\

Function: noun

Etymology: Greek kolla + International Scientific Vocabulary -gen

Date: circa 1865

: any of a group of fibrous proteins that occur in vertebrates as the chief constituent of connective tissue fibrils and in bones and yield gelatin and glue upon boiling with water

— col·lag·e·nous \kə-ˈla-jə-nəs\ adjective