adjectival word-forming element, variant of -al (1) with connective -i-. From Latin -ialis, in which the -i- originally was from the stem of the word being attached but later came to be felt as connective.
I.H.S.
i.n.r.i.
I.Q.
I.R.A.
-ia
-ial
iamb
iambic
-ian
Ian
-iana
