The Collaborative International Dictionary of English v.0.48:

Speak \Speak\, v. i. [imp. Spoke(SpakeArchaic); p. p.
   Spoken(Spoke, Obs. or Colloq.); p. pr. & vb. n.
   Speaking.] [OE. speken, AS. specan, sprecan; akin to
   OF.ries. spreka, D. spreken, OS. spreken, G. sprechen, OHG.
   sprehhan, and perhaps to Skr. sph[=u]rj to crackle, to
   thunder. Cf. Spark of fire, Speech.]
   1. To utter words or articulate sounds, as human beings; to
      express thoughts by words; as, the organs may be so
      obstructed that a man may not be able to speak.
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            Till at the last spake in this manner. --Chaucer.
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            Speak, Lord; for thy servant heareth. --1 Sam. iii.
                                                  9.
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   2. To express opinions; to say; to talk; to converse.
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            That fluid substance in a few minutes begins to set,
            as the tradesmen speak.               --Boyle.
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            An honest man, is able to speak for himself, when a
            knave is not.                         --Shak.
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            During the century and a half which followed the
            Conquest, there is, to speak strictly, no English
            history.                              --Macaulay.
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   3. To utter a speech, discourse, or harangue; to adress a
      public assembly formally.
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            Many of the nobility made themselves popular by
            speaking in Parliament against those things which
            were most grateful to his majesty.    --Clarendon.
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   4. To discourse; to make mention; to tell.
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            Lycan speaks of a part of Caesar's army that came to
            him from the Leman Lake.              --Addison.
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   5. To give sound; to sound.
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            Make all our trumpets speak.          --Shak.
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   6. To convey sentiments, ideas, or intelligence as if by
      utterance; as, features that speak of self-will.
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            Thine eye begins to speak.            --Shak.
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   To speak of, to take account of, to make mention of.
      --Robynson (More's Utopia).

   To speak out, to speak loudly and distinctly; also, to
      speak unreservedly.

   To speak well for, to commend; to be favorable to.

   To speak with, to converse with. "Would you speak with me?"
      --Shak.
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   Syn: To say; tell; talk; converse; discourse; articulate;
        pronounce; utter.
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The Collaborative International Dictionary of English v.0.48:

Speak \Speak\, v. t.
   1. To utter with the mouth; to pronounce; to utter
      articulately, as human beings.
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            They sat down with him upn ground seven days and
            seven nights, and none spake a word unto him. --Job.
                                                  ii. 13.
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   2. To utter in a word or words; to say; to tell; to declare
      orally; as, to speak the truth; to speak sense.
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   3. To declare; to proclaim; to publish; to make known; to
      exhibit; to express in any way.
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            It is my father;s muste
            To speak your deeds.                  --Shak.
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            Speaking a still good morrow with her eyes.
                                                  --Tennyson.
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            And for the heaven's wide circuit, let it speak
            The maker's high magnificence.        --Milton.
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            Report speaks you a bonny monk.       --Sir W.
                                                  Scott.
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   4. To talk or converse in; to utter or pronounce, as in
      conversation; as, to speak Latin.
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            And French she spake full fair and fetisely.
                                                  --Chaucer.
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   5. To address; to accost; to speak to.
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            [He will] thee in hope; he will speak thee fair.
                                                  --Ecclus.
                                                  xiii. 6.
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            each village senior paused to scan
            And speak the lovely caravan.         --Emerson.
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   To speak a ship (Naut.), to hail and speak to her captain
      or commander.
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WordNet (r) 3.0 (2006):

speak
    v 1: express in speech; "She talks a lot of nonsense"; "This
         depressed patient does not verbalize" [syn: talk,
         speak, utter, mouth, verbalize, verbalise]
    2: exchange thoughts; talk with; "We often talk business";
       "Actions talk louder than words" [syn: talk, speak]
    3: use language; "the baby talks already"; "the prisoner won't
       speak"; "they speak a strange dialect" [syn: speak, talk]
    4: give a speech to; "The chairman addressed the board of
       trustees" [syn: address, speak]
    5: make a characteristic or natural sound; "The drums spoke"