Malacia is abnormal softening of a biological tissue, most often cartilage. The word is derived from Greek μαλακός, malakos = soft. Usually the combining form -malacia suffixed to another combining form that denotes the affected tissue assigns a more specific name to each such disorder, as follows: . Osteomalacia (rickets), a bone disorder from vitamin D deficiency . Chondromalacia, softening of cartilage (often refers to chondromalacia patellae when mentioned without further specification) Chondromalacia patellae, a disorder of cartilage under the kneecap .
https://en.wikipedia.org/wiki/Malacia