What is the meaning of ex?

noun

• A man who was formerly a certain woman's husband.
  • synonyms: ex-husband
• A woman who was formerly a particular man's wife.
  • usage: "all his exes live in Texas"
  • synonyms: ex-wife
• The 24th letter of the Roman alphabet.
  • synonyms: X, x

adjective

• Out of fashion.
  • usage: "a suit of rather antique appearance"; "demode (or outmoded) attire"; "outmoded ideas"
  • synonyms: antique, demode, old-fashioned, old-hat, outmoded, passe, passee