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.
Also found in: Dictionary, Thesaurus, Acronyms, Idioms, Encyclopedia, Wikipedia. Related to wonk: Jawn. Informal and somewhat derogatory; a new hire at a Wall Street trading firm. The term was popularized by the book Liar's Poker, which describes the author's experience as a bond trader on Wall Street in the 1980s.