The quality of being accessible; the degree to which something can be reached, approached, or used easily.
From accessible plus -ness. Accessible comes from Latin accessibilis, and -ness is the standard English suffix for creating abstract quality nouns.
While 'accessibility' is the more common form today, 'accessibleness' shows up sometimes in older texts—English speakers can often choose between -ness and -ity suffixes to create similar meanings, reflecting Latin vs. Germanic influences!
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