foursquare (n.)
- biquadratic
- cuboid
- four
- oblong
- open
- quadrate
- quadratic
- quadric
- quadrilateral
- quadruped
- quartic
- quartile
- quaternary
- rhomboid
- square
- straight
- tetrad
- trapezoid
foursquare (adv.)
foursquare (adj.)
- aboveboard
- authentic
- biquadratic
- cube-shaped
- cubic
- cubiform
- cuboid
- diced
- four
- genuine
- oblong
- open
- orthogonal
- quadrangular
- quadrate
- quadratic
- quadrilateral
- quadruped
- quaternary
- rectangular
- rhombic
- rhomboid
- square
- straight
- tetragonal
- tetravalent
- veritable
