Popular Terms. Detailed listing of activities, costs, expected difficulties, and schedules that are required to achieve the objectives of the strategic plans. Because of the quick increase in number of employees the company I work for reviewed their implementation plan for evacuating the building if there is a fire.
Noun. 1. rectangle-a parallelogram with four right angles. foursquare, square - (geometry) a plane rectangle with four equal sides and four right angles; a four-sided regular polygon; you can compute the area of a square if you know the length of its sides.
As such we can say that a square is a  type of rectangle which is a type of shape. We can therefore pass a  square into any function that expects a shape or rectangle object  because a square is covariant with both a rectangle and a shape.