also IRA, 1921, initialism (acronym) for Irish Republican Army, the full name of which attested from 1919.
I.R.A. (2)
also IRA, initialism (acronym) for individual retirement account, attested from 1974.
I.D.
i.e.
I.H.S.
i.n.r.i.
I.Q.
I.R.A.
-ia
-ial
iamb
iambic
-ian