lifework

lifework
    n 1: the principal work of your career
    

42 Moby Thesaurus words for "lifework":
      activity, art, business, calling, campaign, career,
      career building, careerism, cause, commitment, craft, crusade,
      drive, faith, game, great cause, handicraft, interest, issue, line,
      line of business, line of work, mass movement, metier, mission,
      movement, mystery, number, occupation, practice, principle,
      profession, pursuit, racket, reason for being, specialization,
      specialty, trade, vocation, walk, walk of life, work