Ciwon Noonan cuta ce da ke shafar sassan jiki daban-daban. Yana da siffofi na musamman na fuska, irin su idanu da suka yi nisa, ƙarami, da fitaccen goshi, ɗan gajeren tsayi, nakasar ƙirji, nakasar zuciya, da jinkirin ci gaba. Halin yana faruwa ne ta hanyar maye gurbi a cikin kwayoyin halitta da yawa waɗanda ke daidaita haɓakar tantanin halitta da haɓakawa. Sunan ta ne bayan Dokta Jacqueline Noonan, wacce ta fara bayyana yanayin a 1963.