MIAA may refer to: Maine Intercollegiate Athletic Association, defunct athletic conference of schools in Maine Manila International Airport Authority, transportation agency in the Philippines Maryland Interscholastic Athletic Association, high school athletic conference for private schools in the Baltimore Metro area Massachusetts Interscholastic Athletic Association, high school athletic association governing 33 varsity sports throughout Massachusetts Michigan Intercollegiate Athletic Association, athletic conference of NCAA Division III schools in Michigan and Indiana Mid-America Intercollegiate Athletics Association, athletic conference of NCAA Division II schools in Kansas, Missouri, Nebraska, and Oklahoma TRNA dimethylallyltransferase, an enzyme