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

underestimate \un`deres"timate\, v. t.
   to set too low a value on; to estimate below the truth.
   1913 webster

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

underestimate \un`deres"timate\, n.
   the act of underestimating; too low an estimate.
   1913 webster

[3] : WordNet (r) 2.0

underestimate
     n : an estimation that is too low; an estimate that is less than
         the true or actual value syn: underestimation, underrating,
          underreckoning
     v 1: assign too low a value to; "don't underestimate the value of
          this heirlooom-you may sell it at a good price" syn: undervalue
          ant: overvalue, overvalue
     2: make a deliberately low estimate; "the construction company
        wanted the contract badly and lowballed" syn: lowball
     3: make too low an estimate of; "he underestimated the work
        that went into the renovation"; "don't underestimate the
        danger of such a raft trip on this river" syn: underrate
        ant: overestimate
see also:
underestimation underrating underreckoning undervalue overvalue lowball 
underrate overestimate 

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

23 moby thesaurus words for "underestimate":
   belittle, deprecate, depreciate, discount, disparage,
   make light of, make little of, make nothing of, minimize,
   miscalculate, misestimate, misjudge, misprize, sell short,
   set at naught, set little by, shrug off, think little of,
   think nothing of, underprize, underrate, underreckon, undervalue

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