modifiable

from WordNet (r) 3.0 (2006)

modifiable
    adj 1: 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 [ant: {unmodifiable}]

from The Collaborative International Dictionary of English v.0.48

Modifiable \Mod"i*fi`a*ble\, a. [From {Modify}.]
   Capable of being modified; liable to modification.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

34 Moby Thesaurus words for "modifiable":
      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

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