This definition appears somewhat frequently
See other definitions of IAD
Samples in periodicals archive:
INTER-AMERICAN DIVISION. Organized 1922. Territory: Anguilla, Antigua and Barbuda, Aruba, Bahamas, Barbados, Belize, British Virgin Islands, Cayman Islands, Colombia...
The Inter-American Division (IAD) is comprised of Mexico, the Caribbean, Central America and the five northernmost countries of South America.