a prefix from the latin preposition, ex, akin to gr. 'ex or 'ek signifying out of, out, proceeding from. hence, in composition, it signifies out of, as, in exhale, exclude; off, from, or out. as in exscind; beyond, as, in excess, exceed, excel; and sometimes has a privative sense of without, as in exalbuminuos, exsanguinous. in some words, it intensifies the meaning; in others, it has little affect on the signification. it becomes ef- before f, as in effuse. the form e- occurs instead of ex- before b, d, g, l, m, n, r, and v, as in ebullient, emanate, enormous, etc. in words from the french it often appears as es-, sometimes as s- or e-; as, escape, scape, elite.  ex-, prefixed to names implying office, station, condition, denotes that the person formerly held the office, or is out of the office or condition now; as, ex-president, ex-governor, ex-mayor, ex-convict. the greek form 'ex becomes ex in english, as in exarch; 'ek becomes ec, as in eccentric.