Modifiable

Mod´i`fi`a`ble

Capable of being modified; liable to modification.

Adj.

modifiable - capable of being modified in form or character or strength (especially by making less extreme); "the rhythm of physiological time is not modifiable except by interference with certain fundamental processes" - Alexis Carrel

Antonyms:

unmodifiable - incapable of being modified in form or character or strength (especially by making less extreme); "these variations from custom are illogical, incomprehensible, and unmodifiable"

able to adapt, adaptable, adjustable, alterable, alterative, changeable, checkered, convertible, ever-changing, flexible, fluid, impermanent, kaleidoscopic, malleable, many-sided, metamorphic, mobile, movable, mutable, nonuniform, permutable, plastic, protean, proteiform, resilient, resolvable, rubbery, supple, transformable, transient, transitional, transitory, transmutable, variable