c. 1400, "affording access," from Middle French accessible, from Late Latin accessibilis, verbal adjective from Latin accessus "a coming near, approach" (see access (n.)). Meaning "easy to reach" is from 1640s; Of art or writing, "able to be readily understood," 1961 (a term not needed in the years before writing or art often deliberately was made not so).[accessible etymology, accessible origin, 英语词源]