WordNet (r) 3.0 (2006):

in practice
    adv 1: in practical applications; "will this work in practice?"

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "in practice":
   acting, active, at work, functional, functioning, going, going on,
   in commission, in effect, in exercise, in force, in hand,
   in operation, in play, in process, in service, in the works,
   in use, inaction, on foot, on the fire, ongoing, operating,
   operational, running, working