maidan

As a noun square

is (geometry) a polygon with four sides of equal length and four angles of 90 degrees; a regular quadrilateral whose angles are all 90 degrees.

As an adjective square

is shaped like a (the polygon).

As a verb square

is to adjust so as to align with or place at a right angle to something else.

As a noun playground is

(outdoors) a large open space to play on, usually for children.

As an adjective undefined is

lacking a definition or value.

As a noun maida

is a finely milled, refined and bleached wheat flour, used in making many indian foods.

As nouns the difference between maiden and maidan

is that maiden is a girl or an unmarried young woman while maidan is an expanse of open space in or by a city or town.

As an adjective maiden

is virgin.

As a noun taxonomy

is the science or the technique used to make a classification.