[1] : The Collaborative International Dictionary of English v.0.48

ex \ex\ e^ks, n. contraction
   an ex-wife or ex-husband; a former spouse; -- used usually
   with a possessive; as, she invited her ex to her second
   wedding; her ex; his ex; john's ex. informal
   pjc

[2] : The Collaborative International Dictionary of English v.0.48

ex \ex\ e^ks, n.
   the letter x.
   pjc

[3] : The Collaborative International Dictionary of English v.0.48

ex \ex\ e^ks, prep. finance
   without some right; not including the right to have; as, a
   stock selling ex dividend a stock for which the right to a
   dividend has expired the previous day; ex interest; ex
   rights.
   pjc

[4] : The Collaborative International Dictionary of English v.0.48

ex- \ex-\ e^ks.
   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 exalbuminous, 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-wife, ex-convict.
   the greek form 'ex becomes ex in english, as in exarch; 'ek
   becomes ec, as in eccentric.
   1913 webster

[5] : WordNet (r) 2.0

ex
     adj : out of fashion; "a suit of rather antique appearance";
           "demode or outmoded attire"; "outmoded ideas" syn: antique,
            demode, old-fashioned, old-hatp, outmoded, passe,
            passee
     n 1: a man who was formerly a certain woman's husband syn: ex-husband
     2: a woman who was formerly a particular man's wife; "all his
        exes live in texas" syn: exwife
see also:
antique demode old-fashioned old-hatp outmoded passe 
passee ex-husband exwife 

[6] : Moby Thesaurus II by Grady Ward, 1.0

24 moby thesaurus words for "ex":
   aside from, bar, barring, beside, besides, except, except for,
   excepting, excluding, exclusive of, from, leaving out, let alone,
   omitting, out, out of, outside of, precluding, save,
   save and except, saving, than, unless, without

Ex- >> E Words
Ex-, definition of term: Ex-
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