also A1, A-one, "first-rate," 1837 (in Dickens); a figurative use from Lloyd's of London marine insurance company's system for selective rating of merchant vessels ("Register of British and Foreign Shipping"), where it is the designation for ships in first-class condition. The letter refers to the condition of the hull of the ship itself, and the number rating to the equipment. Also used in equivalent ratings in U.S., where colloquially it is sometimes expanded to A No. 1 (which is attested by 1848 as top rating of entries in an agricultural fair).
"catalogue consisting of names in a row or series," c. 1600, from Middle English liste "border, edging, stripe" (late 13c.), from Old French liste "border, band, row, group," also "strip of paper," or from Old Italian lista "border, strip of paper, list," both from Germanic sources (compare Old High German lista "strip, border, list," Old Norse lista "border, selvage," Old English liste "border of cloth, fringe"), from Proto-Germanic *liston, from PIE *leizd- "border, band."
The original Middle English sense is now obsolete. The sense of "enumeration" is from strips of paper used as a sort of catalogue. The native Old English form of the word lingered as list in a few specialized senses. List price is from 1871.