Synonyms for Foursquare (same or very similar meaning)
WordNet sense 1 ((geometry) a plane rectangle with four equal sides and four right angles; a four-sided regular polygon):
square
WordNet sense 2 (firm in purpose or belief; characterized by firmness and determination):
resolute
WordNet sense 3 (with firmness and conviction; without compromise):
squarely, straightforwardly
From the ODE community, based on WordNet
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