sight vs sighting

sight and sighting both are nouns.

Word	Noun	Adjective	Verb	Adverb
sight	Yes	No	Yes	No
sighting	Yes	No	No	No

sight (noun)	sighting (noun)
the act of looking or seeing or observing	the act of observing
the ability to see; the visual faculty
an instance of visual perception
the range of vision
a range of mental vision
a place of interest, especially to visitors
anything that is seen
(often followed by `of') a large number or amount or extent

sight (verb)	sighting (verb)
catch sight of; to perceive with the eyes
take aim by looking through the sights of a gun (or other device)