desertion vs decampment

desertion and decampment both are nouns.

Word	Noun	Adjective	Verb	Adverb
desertion	Yes	No	No	No
decampment	Yes	No	No	No

As nouns, decampment is a hyponym of desertion; that is, decampment is a word with a more specific, narrower meaning than desertion:

Other hyponyms of desertion include abscondment, absence without leave, unauthorized absence, deviationism.

desertion (noun)	decampment (noun)
withdrawing support or help despite allegiance or responsibility	breaking camp
the act of giving something up	the act of running away secretly (as to avoid arrest)