Chessboard array (abbr.), 3 letters
Four-sided figs., 3 letters
Geom. shapes, 3 letters
Geometric figs., 3 letters
Plazas (abbr.), 3 letters
Quilting units: Abbr., 3 letters
Some shapes: abbr., 3 letters
Times and Trafalgar: Abbr., 3 letters
Times and Washington, in New York: abbr., 3 letters
Isolating, 7 letters