The quality or state of being accessible; the ease with which something can be reached, entered, or used.
From accessible plus -ity (making it into an abstract noun). The root is from Latin accessibilis (able to be approached), from accedere (to approach).
This is actually a misspelling of 'accessibility'—notice the 'a' instead of 'i' after the 'c'—but it shows how English speakers sometimes mis-pluralize abstract qualities, creating variant spellings that linguists track!
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