cleaning eye[′klēn·iŋ ‚ī]
1. A pipe fitting with a removable plug which provides access for inspection or cleaning of the pipe run. Also called an access eye or cleaning eye.
2. An opening at the base of a chimney, stack, or breeching for the removal of dust, soot, etc.
3. An opening in concrete forms for removing debris; closed before the concrete is placed.