[1] : The Collaborative International Dictionary of English v.0.48

undertake \un`dertake"\, v. t. imp. undertook; p. p.
   undertaken; p. pr.  vb. n. undertaking. under + take.
   1. to take upon one's self; to engage in; to enter upon; to
      take in hand; to begin to perform; to set about; to
      attempt.
      1913 webster

            to second, or oppose, or undertake
            the perilous attempt.                 --milton.
      1913 webster

   2. specifically, to take upon one's self solemnly or
      expressly; to lay one's self under obligation, or to enter
      into stipulations, to perform or to execute; to covenant;
      to contract.
      1913 webster

            i 'll undertake to land them on our coast. --shak.
      1913 webster

   3. hence, to guarantee; to promise; to affirm.
      1913 webster

            and he was not right fat, i undertake. --dryden.
      1913 webster

            and those two counties i will undertake
            your grace shall well and quietly enjoiy. --shak.
      1913 webster

            i dare undertake they will not lose their labor.
                                                  --woodward.
      1913 webster

   4. to assume, as a character. obs. --shak.
      1913 webster

   5. to engage with; to attack. obs.
      1913 webster

            it is not fit your lordship should undertake every
            companion that you give offense to.   --shak.
      1913 webster

   6. to have knowledge of; to hear. obs. --spenser.
      1913 webster

   7. to take or have the charge of. obs. "who undertakes you
      to your end." --shak.
      1913 webster

            keep well those that ye undertake.    --chaucer.
      1913 webster
see also:
undertook undertaken undertaking 

[2] : WordNet (r) 2.0

undertaken
     see undertake
see also:
undertake 

[3] : WordNet (r) 2.0

undertake
     v 1: enter upon an activity or enterprise syn: set about, attempt
     2: accept as a challenge; "i'll tackle this difficult task"
        syn: tackle, take on
     3: promise to do or accomplish; "guarantee to free the
        prisoners" syn: guarantee
     4: enter into a contractual arrangement syn: contract
     5: accept as a charge syn: take in charge
     also: undertook, undertaken
see also:
set about attempt tackle take on guarantee contract 
take in charge undertook undertaken 

[4] : Moby Thesaurus II by Grady Ward, 1.0

20 moby thesaurus words for "undertaken":
   accepted, agreed, arranged, assumed, chanced, compacted,
   contracted, covenanted, engaged, in hand, in process, in progress,
   in the works, on the anvil, promised, sealed, settled, signed,
   stipulated, under way

Undertaken >> U Words
Undertaken, definition of term: Undertaken
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