The Collaborative International Dictionary of English v.0.48:

Accentuate \Ac*cen"tu*ate\, v. t. [imp. & p. p. Accentuated;
   p. pr. & vb. n. Accentuating.] [LL. accentuatus, p. p. of
   accentuare, fr. L. accentus: cf. F. accentuer.]
   1. To pronounce with an accent or with accents.
      [1913 Webster]

   2. To bring out distinctly; to make prominent; to emphasize.
      [1913 Webster]

            In Bosnia, the struggle between East and West was
            even more accentuated.                --London
                                                  Times.
      [1913 Webster]

   3. To mark with the written accent.
      [1913 Webster]

WordNet (r) 3.0 (2006):

accentuate
    v 1: to stress, single out as important; "Dr. Jones emphasizes
         exercise in addition to a change in diet" [syn: stress,
         emphasize, emphasise, punctuate, accent,
         accentuate]
    2: put stress on; utter with an accent; "In Farsi, you accent
       the last syllable of each word" [syn: stress, accent,
       accentuate]

Moby Thesaurus II by Grady Ward, 1.0:

20 Moby Thesaurus words for "accentuate":
   accent, belabor, dwell on, emphasize, give emphasis to, harp on,
   highlight, italicize, overaccentuate, overemphasize, overstress,
   place emphasis on, point up, punctuate, rub in, spotlight, star,
   stress, underline, underscore