n.1 a the circumference or outline of a closed figure. b the length of this.
2 a the outer boundary of an enclosed area. b a defended boundary.
3 an instrument for measuring a field of vision.
Derivatives:
perimetric adj.
Etymology: F p{eacute}rim{egrave}tre or f. L perimetrus f. Gk perimetros (as PERI-, metros f. metron measure)