(1):

(n.) The noise of slight and frequent cracks or reports; a crackling.

(2):

(n.) A kind of crackling sound or r/le, heard in some abnormal states of the lungs; as, dry crackle; moist crackle.

(3):

(n.) A condition produced in certain porcelain, fine earthenware, or glass, in which the glaze or enamel appears to be cracked in all directions, making a sort of reticulated surface; as, Chinese crackle; Bohemian crackle.

(4):

(v. i.) To make slight cracks; to make small, sharp, sudden noises, rapidly or frequently repeated; to crepitate; as, burning thorns crackle.