As adjectives the difference between causal and noncausal

is that causal is of, relating to, or being a cause of something; causing while noncausal is not causal.

As a noun causal

is (grammar) a word (such as because) that expresses a reason or a cause.

As adjectives the difference between casual and noncasual

is that casual is happening by chance while noncasual is not casual.

As a noun casual

is (british|nz) a worker who is only working for a company occasionally, not as its permanent employee.

As a proper noun constant

is .

As an adjective nonconstant is

not constant.

As a noun perimeter

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

As an adjective isoperimetric is

having the same perimeter; applied to the problem of finding a plane figure of the largest possible area whose boundary has a specified length.

As an adverb plane

is (label) particularly, especially, certainly.

As a noun plane

is (label) the thing, the point, the interesting thing, the main interest in something, unusualness, speciality.

As an adjective isoperimetric is

(geometry) having the same perimeter; applied to the problem of finding a plane figure of the largest possible area whose boundary has a specified length.

As adjectives the difference between figure and isoperimetric

is that figure is figurative while isoperimetric is (geometry) having the same perimeter; applied to the problem of finding a plane figure of the largest possible area whose boundary has a specified length.

As a verb figure

is .

As a noun boundary

is the dividing line or location between two areas.

As an adjective isoperimetric is

(geometry) having the same perimeter; applied to the problem of finding a plane figure of the largest possible area whose boundary has a specified length.

As a noun length

is the distance measured along the longest dimension of an object.

As a verb length

is (obsolete) to lengthen.

As an adjective isoperimetric is

(geometry) having the same perimeter; applied to the problem of finding a plane figure of the largest possible area whose boundary has a specified length.

As adjectives the difference between atomic and nonatomic

is that atomic is atomic while nonatomic is not atomic.

As adjectives the difference between metameric and nonmetameric

is that metameric is (biology) exhibiting metamerism while nonmetameric is not metameric.