desm(o)-

A bond or chain.

Greek desmos, a chain or fetter; desme, bundle.

A desmosome is a structure by which two adjacent cells are attached, formed from protein plaques in the cell membranes linked by filaments; desmoid denotes a type of fibrous tumour of muscle and connective tissue, typically in the abdomen; a desmid is a single-celled freshwater alga which appears to be composed of two rigid cells with a shared nucleus.