What is (a) A grating or crackling sensation or sound, as that produced by rubbing two fragments of a broken bone together, or by pressing upon cellular tissue containing air. (b) A crepitant râle called?

crepitation — (Med.) (a) A grating or crackling sensation or sound, as that produced by rubbing two fragments of a broken bone together, or by pressing upon cellular tissue containing air. (b) A crepitant râle. (Webster's 1913.)

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