discretion vs sagacity

discretion and sagacity both are nouns.

Word	Noun	Adjective	Verb	Adverb
discretion	Yes	No	No	No
sagacity	Yes	No	No	No

As nouns, sagacity is a hypernym of discretion; that is, sagacity is a word with a broader meaning than discretion:

discretion: knowing how to avoid embarrassment or distress
sagacity: the mental ability to understand and discriminate between relations

Other hypernyms of discretion include discernment, judgement, judgment, sagaciousness.

discretion (noun)	sagacity (noun)
the trait of judging wisely and objectively	the trait of forming opinions by distinguishing and evaluating
the power of making free choices unconstrained by external agencies	the mental ability to understand and discriminate between relations
knowing how to avoid embarrassment or distress
refined taste; tact
freedom to act or judge on one's own