Synonyms for Perspicacity (same or very similar meaning)
WordNet sense 1 (intelligence manifested by being astute (as in business dealings)):
astuteness, shrewdness, perspicaciousness
WordNet sense 2 (the capacity to assess situations or circumstances shrewdly and to draw sound conclusions):
judgment, judgement, sound judgement, sound judgment
From the ODE community, based on WordNet
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