Is it farther or further?
early 14c., originally past participle of afray "frighten," from Anglo-French afrayer, from Old French esfreer (see affray (n.)). A rare case of an English adjective that never stands before a noun. Because it was used in A.V. Bible, it acquired independent standing and thrived while affray faded, chasing out the once more common afeared. Sense in I'm afraid "I regret to say, I suspect" (without implication of fear) is first recorded 1590s.
Her blue affrayed eyes wide open shone [Keats, "The Eve of St. Agnes," 1820]