stratagem vs strategy

stratagem and strategy both are nouns.

Word	Noun	Adjective	Verb	Adverb
stratagem	Yes	No	No	No
strategy	Yes	No	No	No

As nouns, strategy is a hypernym of stratagem; that is, strategy is a word with a broader meaning than stratagem:

Other hypernyms of stratagem include scheme.

stratagem (noun)	strategy (noun)
a maneuver in a game or conversation	an elaborate and systematic plan of action
an elaborate or deceitful scheme contrived to deceive or evade	the branch of military science dealing with military command and the planning and conduct of a war