Synonyms for Changeable (same or very similar meaning)
WordNet sense 1 (subject to change):
uncertain, unsettled
WordNet sense 2 (liable to or capable of change):
variable
WordNet sense 3 (varying in color when seen in different lights or from different angles):
chatoyant, iridescent, shot
WordNet sense 4 (having striking color):
colorful, colourful
WordNet sense 5 (capable of or tending to change in form or quality or nature):
mutable
WordNet sense 6 (tending to vary often or widely):
volatile
WordNet sense 7 (capable of changing quickly from one state or condition to another):
mobile, mobile
WordNet sense 8 (continually shifting or rapidly changing):
kaleidoscopic
WordNet sense 9 (affording change (especially in social status)):
fluid
WordNet sense 10 (subject to change; variable):
unstable
WordNet sense 11 (liable to sudden unpredictable change):
erratic, fickle, mercurial
WordNet sense 12 (such that alteration is possible; having a marked tendency to change):
changeful
From the ODE community, based on WordNet
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