sighting

[n] - the act of observing
Found on http://www.webdictionary.co.uk/definition.php?query=sighting

Sighting

Sight'ing adjective & noun from Sight , transitive verb Sighting shot , a shot made to ascertain whether the sights of a firearm are properly adjusted; a trial shot.
Found on http://www.encyclo.co.uk/webster/S/100

sighting

noun the act of observing; `several sightings of enemy troops were reported`
Found on http://wordnetweb.princeton.edu/perl/webwn?s=sighting

Sighting

• (p. pr. & vb. n.) of Sight • a. & n. from Sight, v. t.
Found on http://thinkexist.com/dictionary/meaning/sighting/
No exact match found