Need to know the distance all the way around a figure? This StudyJams! activity will teach students to calculate perimeter. Synonyms for perimeter at Thesaurus.com with free online thesaurus, antonyms, and definitions. Find descriptive alternatives for perimeter. Explore Area and Perimeter at Math Playground! Learn how to find the area and perimeter of rectangles. PERIMETER INSTITUTE RECORDED SEMINAR ARCHIVE. Home Help Advanced search Send Feedback. To find the perimeter of an object, Adam Ant adds the lengths of the sides of the object. Learn about perimeter the fun way in this Shape Game Geometry An interactive math lesson calculating the perimeter of a square. Perimeter Institute for Theoretical Physics (PI, Perimeter, PITP) is an independent research centre in foundational theoretical physics located in Waterloo, Ontario. Formed in 1998, Perimeter Security Group is a woman-owned small business contractor that has become one of the leading providers of physical security systems.