AIDS is defined as an abbreviation for for Acquired Immune Deficiency Syndrome and is caused by the HIV virus.
An example of AIDS is the first case - Patient O - a Canadian flight attendant to whom all the initial cases can be traced as having had contact with the air steward.
See AIDS in Webster's New World College Dictionary
Origin: A(cquired) I(mmune) D(eficiency) S(yndrome)
See AIDS in American Heritage Dictionary 4
Origin: a(cquired) i(mmune) d(eficiency) s(yndrome).
Learn more about AIDS