The Collaborative International Dictionary of English v.0.48:

Take off \Take" off`\, v. i.
   1. to begin a leap from a surface or a flight into the air;
      especially, (of a bird or an airplane) to leave the ground
      and begin to fly; as, flight CA123 took off on schedule at
      3:00 PM.
      [PJC]

   2. To begin a period of accelerating growth or development;
      as, the economy took off in the third quarter.
      [PJC]

   3. To begin a journey; to depart.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Take off \Take" off`\, v. t.
   1. To remove, as from the surface or outside; to remove from
      the top of anything; as, to take off a load; to take off
      one's hat, coat or other article of clothing; to take off
      a coat of paint from a surface.
      [1913 Webster +PJC]

   2. To cut off; as, to take off the head, or a limb.
      [1913 Webster]

   3. To destroy; as, to take off life.
      [1913 Webster]

   4. To remove; to invalidate; as, to take off the force of an
      argument.
      [1913 Webster]

   5. To withdraw; to call or draw away; as, the director took
      him off the project. --Locke.
      [1913 Webster + PJC]

   6. To swallow; as, to take off a glass of wine.
      [1913 Webster]

   7. To purchase; to take in trade. "The Spaniards having no
      commodities that we will take off." --Locke.
      [1913 Webster]

   8. To copy; to reproduce. "Take off all their models in
      wood." --Addison.
      [1913 Webster]

   9. To imitate; to mimic; to personate.
      [1913 Webster]

   10. To find place for; to dispose of; as, more scholars than
       preferments can take off. [R.] --Bacon.
       [1913 Webster]

   11. To discount or deduct (from a price); the dealer took off
       twenty percent on remaining toys.
       [PJC]

WordNet (r) 3.0 (2006):

take off
    v 1: leave; "The family took off for Florida" [syn: depart,
         part, start, start out, set forth, set off, set
         out, take off]
    2: take away or remove; "Take that weight off me!"
    3: depart from the ground; "The plane took off two hours late"
       [syn: take off, lift off]
    4: take time off from work; stop working temporarily [syn: take
       off, take time off]
    5: mimic or imitate in an amusing or satirical manner; "This
       song takes off from a famous aria"
    6: remove clothes; "take off your shirt--it's very hot in here"
    7: get started or set in motion, used figuratively; "the project
       took a long time to get off the ground" [syn: get off the
       ground, take off]
    8: prove fatal; "The disease took off"
    9: make a subtraction; "subtract this amount from my paycheck"
       [syn: subtract, deduct, take off] [ant: add, add
       together]