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

although \although"\, conj. all + though; oe. al thagh.
   grant all this; be it that; supposing that; notwithstanding;
   though.
   1913 webster

         although all shall be offended, yet will not i. --mark
                                                  xiv. 29.
   1913 webster

   syn: although, though.

   usage: although, which originally was perhaps more emphatic
          than though, is now interchangeable with it in the
          sense given above. euphonic consideration determines
          the choice.
          1913 webster
see also:
although though 

[2] : WordNet (r) 2.0

although
     adv : despite the fact that; "even though she knew the answer, she
           did not respond" syn: though, tho'
see also:
though tho' 

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

25 moby thesaurus words for "although":
   after all, again, albeit, all the same, at all events, at any rate,
   but, even, even so, for all that, howbeit, however, in any case,
   in any event, just the same, nevertheless, nonetheless,
   notwithstanding, rather, still, though, when, whereas, while,
   yet

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