noun.
The act of catching sight of something, especially something searched for
verb.
Present participle of sight.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
noun.
the act of observing
Word Usage
"The _sighting notch_ in the slide with the rear sight leaf down, is the same height as is the sighting in the drift slide when the rear sight leaf is raised and set at 530 yards."