Used to label an unusually large number of occurrances of a disease or condition in one place. An autism cluster would be an unusually large number of cases of autism in (perhaps) a single locality. Clusters constitute evidence in the search for causes of diseases and conditions.
Top definition. jawn. a word used by Philly cats to describe anything and everything. NY cats interject with the word joint but it doesn't convey the same feelings.
: jaw 1a. 2. a: an upper jaw especially of humans or other mammals in which the bony elements are closely fused b: either of two membrane bone elements of the upper jaw that lie lateral to the premaxillae and that in higher vertebrates including humans bear most of the teeth.3.edical Definition of MAXILLA. 1. : jaw 1a. 2. a: an upper jaw especially of humans or other mammals in which the bony elements are closely fused b: either of two membrane bone elements of the upper jaw that lie lateral to the premaxillae and that in higher vertebrates including humans bear most of the teeth. 3.