The Collaborative International Dictionary of English v.0.48:

Insinuate \In*sin"u*ate\, v. i.
   1. To creep, wind, or flow in; to enter gently, slowly, or
      imperceptibly, as into crevices.
      [1913 Webster]

   2. To ingratiate one's self; to obtain access or favor by
      flattery or cunning.
      [1913 Webster]

            He would insinuate with thee but to make thee sigh.
                                                  --Shak.
      [1913 Webster]

            To insinuate, flatter, bow, and bend my limbs.
                                                  --Shak.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Insinuate \In*sin"u*ate\, v. t. [imp. & p. p. Insinuated; p.
   pr. & vb. n. Insinuating.] [L. insinuatus, p. p. of
   insinuareto insinuate; pref. in- in + sinus the bosom. See
   Sinuous.]
   [1913 Webster]
   1. To introduce gently or slowly, as by a winding or narrow
      passage, or a gentle, persistent movement.
      [1913 Webster]

            The water easily insinuates itself into, and
            placidly distends, the vessels of vegetables.
                                                  --Woodward.
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   2. To introduce artfully; to infuse gently; to instill.
      [1913 Webster]

            All the art of rhetoric, besides order and
            clearness, are for nothing else but to insinuate
            wrong ideas, move the passions, and thereby mislead
            the judgment.                         --Locke.
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            Horace laughs to shame all follies and insinuates
            virtue, rather by familiar examples than by the
            severity of precepts.                 --Dryden.
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   3. To hint; to suggest by remote allusion; -- often used
      derogatorily; as, did you mean to insinuate anything?
      [1913 Webster]

   4. To push or work (one's self), as into favor; to introduce
      by slow, gentle, or artful means; to ingratiate; -- used
      reflexively.
      [1913 Webster]

            He insinuated himself into the very good grace of
            the Duke of Buckingham.               --Clarendon.

   Syn: To instill; hint; suggest; intimate.
        [1913 Webster]

WordNet (r) 3.0 (2006):

insinuate
    v 1: introduce or insert (oneself) in a subtle manner; "He
         insinuated himself into the conversation of the people at
         the nearby table"
    2: give to understand; "I insinuated that I did not like his
       wife" [syn: intimate, adumbrate, insinuate]

Moby Thesaurus II by Grady Ward, 1.0:

155 Moby Thesaurus words for "insinuate":
   accuse, adumbrate, allege, allegorize, allude to, arraign, article,
   ascribe, assume, barge in, book, break in, break in upon,
   bring accusation, bring charges, bring to book, bring to mind,
   burst in, butt in, charge, charge in, cite, come between, complain,
   connote, convey, crash, crash in, crash the gates, creep in,
   crowd in, cut in, denounce, denunciate, drag in, drop a hint,
   ease in, edge in, elbow in, encroach, entail, entrench, fasten on,
   fasten upon, fill in, finger, foist, foist in, fudge in,
   give a hint, give the cue, glance at, hang something on, hint,
   hint at, horn in, impeach, impinge, implant in, implicate, imply,
   import, impose, impose on, impose upon, impute, indicate, indict,
   infer, infiltrate, inform against, inform on, infringe, infuse,
   inject, inject in, inoculate, insert, insert in, insinuate in,
   intercalate, interfere, interjaculate, interject, interlope,
   interpolate, interpose, intervene, intimate, introduce,
   introduce in, intromit, intrude, invade, involve, irrupt,
   lay charges, lodge a complaint, lodge a plaint, lug in, mean,
   mean to say, obtrude, perfuse, pin on, point indirectly to, pop in,
   prefer charges, press charges, press in, presume, presuppose,
   prompt, push in, put between, put in, put on, put on report,
   put upon, report, reproach, run in, rush in, sandwich, set in,
   signify, slink in, slip in, smash in, smuggle in, sneak in,
   squeeze in, steal in, stick in, storm in, suggest, suppose,
   take for granted, take to task, task, taunt with, tax, throng in,
   throw in, thrust in, trench, trespass, tuck in, twit, wedge in,
   whip in, whisper, work in, worm, worm in