I am unable to find the MO comments about the first use of the phrase "fat slags" in an article. [On page 26 of this](http://arxiv.org/abs/math/0104196) we find "these correspond to thickenings of the
corresponding special Lagrangian (giving fat SLags, as they are known in Britain,
or multiply-wrapped cycles in physics speak)."


As this arXiv paper is 2001, the whole business long precedes the beginning of MO in any case; what I remember is at least one comment expressing astonishment that the authors who invented the term fat SLags actually were able to put it in a real mathematics/physics paper without screams from a referee. 


Anyway, this may be going into a survey talk for amateurs. Something juicy, you see. 



Special Lagrangians and fat
This answer and its comments, is the reference you are searching for:
<https://mathoverflow.net/a/22384/2051>


The paper in which the term appears appears is <http://arxiv.org/abs/math.DG/0104196>


