ex /(ĕks)/

ex

n.
  1. 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. [contraction]

ex

n.
  1. The letter x.

ex

prep.
  1. 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. (Finance)