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Medical Term:


Pronunciation: ton'o-fil'a-ment


A structural cytoplasmic protein, of a class known as intermediate filaments, bundles of which together form a tonofibril; a tonofilament is made up of a variable number of related proteins, keratins, and is found in all epithelial cells, but is particularly well developed in the epidermis.

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.