ir-

Multiple Entries:
  ir-    in-  

Concise Oxford English Dictionary © 2008 Oxford University Press:
ir-

▶prefix variant spelling of in-1, in-2. assimilated before r (as in irradiate).

Concise Oxford English Dictionary © 2008 Oxford University Press:
in-1 (also il- before l; im- before b, m, p; ir- before r)

▶prefix

• 1 (added to adjectives) not: infertile.

• 2 (added to nouns) without; a lack of: inappreciation.

– origin from L.

Concise Oxford English Dictionary © 2008 Oxford University Press:
in-2 (also il- before l; im- before b, m, p; ir- before r)

▶prefix in; into; towards; within: influx.

– origin representing in or the L. prep. in.