(a) An additional name [cp. surname n. (a)]; also, an epithet; a family name or last name [quots. 1472-3 & prob. a1425]; (b) a distinguishing name; also, a pseudonym, nom de guerre [last quot.].
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A prefix in words derived primarily from L, occ. from OF, or from both, often with its original meaning still discernible: (a) 'subordinate or inferior in rank' (in nouns): subcelerer,……