Source : Webster's Revised Unabridged Dictionary (1913)

Dilate \Di*late"\ (?; 277), v. t. [imp. & p. p. {Dilated}; p.
   pr. & vb. n. {Dilating}.] [L. dilatare; either fr. di- = dis-
   + latus wide, not the same word as latus, used as p. p. of
   ferre to bear (see {Latitude}); or fr. dilatus, used as p. p.
   of differre to separate (see {Delay}, {Tolerate}, {Differ},
   and cf. {Dilatory}): cf. F. dilater.]
   1. To expand; to distend; to enlarge or extend in all
      directions; to swell; -- opposed to {contract}; as, the
      air dilates the lungs; air is dilated by increase of heat.

   2. To enlarge upon; to relate at large; to tell copiously or
      diffusely. [R.]

            Do me the favor to dilate at full What hath befallen
            of them and thee till now.            --Shak.

   Syn: To expand; swell; distend; enlarge; spread out; amplify;
        expatiate.

Dilated \Di*lat"ed\, a.
   1. Expanded; enlarged. --Shak.

   2. (Bot.) Widening into a lamina or into lateral winglike
      appendages.

   3. (Zo["o]l.) Having the margin wide and spreading.

Source : WordNet®

dilated
     adj : made wider or larger in all dimensions; "a dilated pupil"