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

approximately \approx"imately\, adv.
   with approximation; so as to approximate; nearly.
   1913 webster

[2] : WordNet (r) 2.0

approximately
     adv : of quantities imprecise but fairly close to correct;
           "lasted approximately an hour"; "in just about a
           minute"; "he's about 30 years old"; "i've had about all
           i can stand"; "we meet about once a month"; "some forty
           people came"; "weighs around a hundred pounds";
           "roughly $3,000"; "holds 3 gallons, more or less"; "20
           or so people were at the party" syn: about, close
           to, just about, some, roughly, more or less, around,
            or so
see also:
about close to just about some roughly more or less 
around or so 

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

39 moby thesaurus words for "approximately":
   about, all but, all in all, almost, almost entirely, approaching,
   approximatively, around, by and large, chiefly, circa, close to,
   effectually, essentially, for practical purposes, generally,
   generally speaking, in round numbers, in the main, mainly,
   more or less, most, mostly, much, nearabout, nearly, nigh,
   on balance, on the whole, plus ou moins, practically, roughly,
   roughly speaking, roundly, say, some, substantially, virtually,
   well-nigh

Approximately >> A Words
Approximately, definition of term: Approximately
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