Capable of being augmented or increased.(adjective)
Capable of increasing.(adjective)
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Use "augmentable" in a sentence
"The ultimate scarcity must be that of labour or of land (or both); formally, it must be scarcity of some non-augmentable factor of production."
"The more important factor for investors to consider is that Xinyuan's recent proactive actions are sustainable if not augmentable."
"The magic items section of the book includes mostly psionic based armor, weapons, and implements that have augmentable powers, and ki focuses for the monk (and assassin) classes."