The Collaborative International Dictionary of English v.0.48:

aerodynamics \aer`o*dy*nam"ics\ Aerodynamics
\A`["e]r*o*dy*nam"ics\, n. [A["e]ro- + dynamics: cf. F.
   a['e]rodynamique.]
   The science which treats of the air and other gaseous bodies
   under the action of force, and of their mechanical effects.
   [1913 Webster]

WordNet (r) 3.0 (2006):

aerodynamics
    n 1: the branch of mechanics that deals with the motion of gases
         (especially air) and their effects on bodies in the flow
         [syn: aeromechanics, aerodynamics]