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

aesthetics \aesthet"ics\, esthetics \esthet"ics\ ?; 277,
   n. gr. ? perceptive, esp. by feeling, fr. ? to perceive,
   feel: cf. g. aumsthetik, f. esth'etique.
   the theory or philosophy of taste; the science of the
   beautiful in nature and art; esp. that which treats of the
   expression and embodiment of beauty by art.
   1913 webster

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

esthete \es"thete\, n.; esthetic \esthet"ic\, a., esthetical
\esthet"ical\, a., esthetics \esthet"ics\, n. etc.
   same as aesthete, aesthetic, aesthetical,
   aesthetics, etc.
   1913 webster
see also:
aesthete aesthetic aesthetical aesthetics 

[3] : WordNet (r) 2.0

esthetics
     n : art the branch of philosophy dealing with beauty and taste
         emphasizing the evaluative criteria that are applied to
         art; "traditional aesthetics assumed the existence of
         universal and timeless criteria of artistic value" syn:
         aesthetics
see also:
aesthetics 

Esthetics >> E Words
Esthetics, definition of term: Esthetics
esthetics_pag1.html