The Oxford Thesaurus An A-Z Dictionary of Synonyms - veteran n.

1) old hand, past master, old-timer, trouper, Colloq warhorse: Barlow was a veteran of twenty years' experience in the service. --adj. 2) experienced, practised, seasoned, mature, long-serving, battle-scarred: Did it never occur to this veteran politician that there are degrees of misconduct?