ENGLISH
REFERENCE

perimeter

n. countable
B2 Upper Intermediate US //pɝˈɪmətɝ// UK //pəɹˈɪmɪtɐ// perime·ter

n. the total distance around the outside edge of a shape or area. You can find it by adding the lengths of all the sides together.

n. the continuous line forming the boundary of a closed geometric figure or a specific area. In a military or security context, it refers to the outer limits of a protected position.


SIMPLE

The perimeter of the square garden is twenty meters.

CONTEXTUAL

Security guards patrol the perimeter of the warehouse every hour to check for broken fences.

COMPLEX

Calculating the perimeter of an irregular polygon requires the precise measurement of every individual segment before summing them to find the total boundary length.

Synonyms
Origin

From Latin perimetros, Ancient Greek περίμετρος (perímetros). Equivalent to peri- + meter.

Usage

Often used with the verbs 'patrol', 'secure', or 'calculate'.

Pitfall

the perimeter from the circlethe perimeter of the circleUse the preposition 'of' to link the perimeter to the object it bounds.

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