The Collaborative International Dictionary of English v.0.48:

Clatter \Clat"ter\, v. i. [imp. & p. p. Clattered; p. pr. &
   vb. n. Clattering.] [AS. cla?rung a rattle, akin to D.
   klateren to rattle. Cf. Clack.]
   1. To make a rattling sound by striking hard bodies together;
      to make a succession of abrupt, rattling sounds.
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            Clattering loud with iron clank.      --Longfellow.
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   2. To talk fast and noisily; to rattle with the tongue.
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            I see thou dost but clatter.          --Spenser.
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The Collaborative International Dictionary of English v.0.48:

Clatter \Clat"ter\, v. t.
   To make a rattling noise with.
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         You clatter still your brazen kettle.    --Swift.
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The Collaborative International Dictionary of English v.0.48:

Clatter \Clat"ter\, n.
   1. A rattling noise, esp. that made by the collision of hard
      bodies; also, any loud, abrupt sound; a repetition of
      abrupt sounds.
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            The goose let fall a golden egg
            With cackle and with clatter.         --Tennyson.
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   2. Commotion; disturbance. "Those mighty feats which made
      such a clatter in story." --Barrow.
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   3. Rapid, noisy talk; babble; chatter. "Hold still thy
      clatter." --Towneley Myst. (15 th Cent. ).
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            Throw by your clatter
            And handle the matter.                --B. Jonson
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WordNet (r) 3.0 (2006):

clatter
    n 1: a rattling noise (often produced by rapid movement); "the
         shutters clattered against the house"; "the clatter of iron
         wheels on cobblestones"
    v 1: make a rattling sound; "clattering dishes" [syn: clatter,
         clack, brattle]