A hardened area of the skin (especially on the foot or hand) caused by repeated friction, wear or use.
A shining area on the frons of many species of Tabanomorpha (horse flies and relatives).
The material of repair in fractures of bone; a substance exuded at the site of fracture, which is at first soft or cartilaginous in consistency, but is ultimately converted into true bone and unites the fragments into a single piece.
The new formation over the end of a cutting, before it puts out rootlets.
To form such hardened tissue.
The repeated striking of an object to break or shape it, as in percussion drilling.
The detonation of a percussion cap in a firearm.
The tapping of the body as an aid to medical diagnosis.
The sound so produced.
The outer side of the hand.
The collision of two bodies in order to produce a sound.
The section of an orchestra or band containing percussion instruments; such instruments considered as a group; in bands, may be separate from drum kits.