The quality or state of being obtainable or able to be acquired; the degree to which something is gettable.
From 'gettable' (get + -able) plus the suffix '-ness' (Old English '-nes'), forming an abstract noun describing the quality of obtainability.
Adding '-ness' to adjectives to create abstract nouns is so natural in English that we can generate words like this almost automatically—'gettableness' works instantly in a sentence even if no one's ever said it before.
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