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

tantamount \tan"tamount`\, a. f. tant so much l. tantus + e.
   amount.
   equivalent in value, signification, or effect.
   1913 webster

         a usage nearly tantamount to constitutional right.
                                                  --hallam.
   1913 webster

         the certainty that delay, under these circumstances,
         was tantamount to ruin.                  --de quincey.
   1913 webster

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

tantamount \tan"tamount`\, v. i.
   to be tantamount or equivalent; to amount. obs. --jer.
   taylor.
   1913 webster

[3] : WordNet (r) 2.0

tantamount
     adj : being essentially equal to something; "it was as good as
           gold"; "a wish that was equivalent to a command"; "his
           statement was tantamount to an admission of guilt"
           syn: equivalent, tantamountp
see also:
equivalent tantamountp 

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

28 moby thesaurus words for "tantamount":
   alike, all one, all the same, analogous, answering, coequal,
   complemental, complementary, convertible, coordinate,
   correspondent, corresponding, duplicate, equal, equiparant,
   equipollent, equivalent, homologous, identic, identical,
   indistinguishable, like, much the same, reciprocal, reciprocative,
   selfsame, uniform, very

Tantamount >> T Words
Tantamount, definition of term: Tantamount
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Tantamount To >> T Words
Tantamount To, definition of term: Tantamount To
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