Which quad words means a playground with four sides?

one of these

quadding quadplex

quadplexes

quadrangle quadrangles quadrangular quadrans

quadrant quadrantal

quadrantes

quadrants quadraphonic quadraphonics quadrat

quadrate

quadrated

quadrates

quadratic quadratically quadratics quadrating

quadrats

quadrature quadratures quadrennia

quadrennial quadrennially

quadrennials

quadrennium quadrenniums quadric

quadricentennial

quadricentennials

quadriceps quadricepses quadrics

quadriga

quadrigae

quadrilateral quadrilaterals quadrille quadrilles quadrillion quadrillions quadrillionth

quadrillionths

quadripartite quadriphonic

quadriphonics

quadriplegia quadriplegias

quadriplegic quadriplegics quadrivalent

quadrivalents

quadrivia

quadrivial

quadrivium quadriviums

quadroon

quadroons

quadrumanous

quadrumvir

quadrumvirate

quadrumvirates

quadrumvirs

quadruped quadrupedal quadrupeds quadruple quadrupled quadruples quadruplet quadruplets quadruplicate quadruplicated quadruplicates quadruplicating quadruplication quadruplications

quadruplicities

quadruplicity

quadrupling quadruply quadrupole quadrupoles