Synonyms for Expansible (same or very similar meaning)
WordNet sense 1 (able to expand or be expanded):
expandable, expandible
WordNet sense 2 (able or tending to expand or characterized by expansion):
expansive
WordNet sense 3 ((of gases) capable of expansion):
expansile
WordNet sense 4 (capable of resuming original shape after stretching or compression; springy):
elastic
From the ODE community, based on WordNet
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