WordNet (r) 3.0 (2006):

work out
    v 1: come up with; "His colleagues worked out his interesting
         idea"; "We worked up an ad for our client" [syn: work
         out, work up]
    2: happen in a certain way, leading to, producing, or resulting
       in a certain outcome, often well; "Things worked out in an
       interesting way"; "Not everything worked out in the end and
       we were disappointed"
    3: work out in detail; "elaborate a plan" [syn: elaborate,
       work out]
    4: do physical exercise; "She works out in the gym every day"
       [syn: exercise, work out]
    5: be calculated; "The fees work out to less than $1,000"
    6: make a mathematical calculation or computation [syn:
       calculate, cipher, cypher, compute, work out,
       reckon, figure]
    7: find the solution to (a problem or question) or understand
       the meaning of; "did you solve the problem?"; "Work out your
       problems with the boss"; "this unpleasant situation isn't
       going to work itself out"; "did you get it?"; "Did you get my
       meaning?"; "He could not work the math problem" [syn:
       solve, work out, figure out, puzzle out, lick,
       work]
    8: give a workout to; "Some parents exercise their infants"; "My
       personal trainer works me hard"; "work one's muscles"; "this
       puzzle will exercise your mind" [syn: exercise, work,
       work out]

Moby Thesaurus II by Grady Ward, 1.0:

183 Moby Thesaurus words for "work out":
   accommodate, accomplish, achieve, add, adjust, algebraize, amplify,
   answer, arrange, attain, attend, become of, bottom, bring off,
   calculate, carry into effect, carry into execution, carry off,
   carry out, carry through, cast, cipher, clear up, close,
   close with, come about, come of, come out, come through, compass,
   complete, compose, compute, concert, conclude, consummate,
   contrive, crack, cut out, deal with, debug, decipher, decode,
   descant, design, detail, develop, devise, dilate, discharge,
   disentangle, dispatch, dispose of, divide, divine, do, do the job,
   do the trick, dope, dope out, effect, effectuate, elaborate, enact,
   end, enlarge, enlarge upon, ensue, enter into detail, estimate,
   eventuate, evolve, execute, expand, expatiate, explain, explicate,
   extract roots, fall out, fare, fathom, fetch, figure, figure in,
   figure out, find out, find the answer, find the solution, fix,
   follow, forecast, frame, fulfill, get, get right, get through,
   go into, go through, guess, guess right, have it, hit it,
   implement, intend, interpret, issue, knock off, labor, lay plans,
   make, make a projection, make arrangements, make out, make up,
   manage, measure, methodize, multiply, open the lock, organize,
   pan out, particularize, perform, plan, plan ahead, plumb,
   polish off, prearrange, produce, program, project, prove,
   prove to be, psych, psych out, put away, put in practice,
   put into effect, put into practice, put through, puzzle out,
   rationalize, ravel, ravel out, realize, reckon,
   rehearse in extenso, relate at large, resolve, result, riddle,
   schedule, schematize, score, set up, settle, settle with, shape,
   solve, sort out, spell out, straighten out, subtract, succeed,
   systematize, take account of, take care of, tally, terminate,
   translate into action, turn out, turn the trick, undo, unfold,
   unlock, unravel, unriddle, unscramble, untangle, untwist, unweave,
   work, work up