Perimeter

A perimeter is a path that surrounds a two-dimensional shape. The term may be used either for the path or its lengthâ€”it can be thought of as the length of the outline of a shape. The perimeter of a circle or ellipse is called its circumference.

Calculating the perimeter has several practical applications. A calculated perimeter is the length of fence required to surround a yard or garden. The perimeter of a wheel (its circumference) describes how far it will roll in one revolution. Similarly, the amount of string wound around a spool is related to the spool’s perimeter.

**Wikipedia**

Boundary (noun)

The dividing line or location between two areas.

Boundary (noun)

An edge or line marking an edge of the playing field.

Boundary (noun)

An event whereby the ball is struck and either touches or passes over a boundary (with or without bouncing), usually resulting in an award of 4 (four) or 6 (six) runs respectively for the batting team.

Boundary (noun)

The set of points in the closure of a set S, not belonging to the interior of that set.

Perimeter (noun)

The sum of the distance of all the lengths of the sides of an object.

Perimeter (noun)

The length of such a boundary.

Perimeter (noun)

The outer limits of an area. circumference

Perimeter (noun)

A fortified strip or boundary usually protecting a military position.

Perimeter (noun)

An instrument for determining the extent and shape of the field of vision.

**Wiktionary**

Boundary (noun)

a line which marks the limits of an area; a dividing line

“a county boundary”

“a boundary wall”

“the river marks the boundary between the two regions”

Boundary (noun)

a limit of something abstract, especially a subject or sphere of activity

“a community without class or political boundaries”

Boundary (noun)

a hit crossing the limits of the field, scoring four or six runs.

Perimeter (noun)

the continuous line forming the boundary of a closed geometrical figure

“the perimeter of a rectangle”

Perimeter (noun)

the outermost parts or boundary of an area or object

“a perimeter fence”

“the perimeter of the garden”

Perimeter (noun)

an area away from the basket, beyond the reach of the defensive team

“he was very patient in working the ball around the perimeter”

Perimeter (noun)

an instrument for measuring the extent and characteristics of a person’s field of vision.

**Oxford Dictionary**