The Collaborative International Dictionary of English v.0.48:

Loud \Loud\ (loud), a. [Compar. Louder (loud"[~e]r); superl.
   Loudest.] [OE. loud, lud, AS. hl[=u]d; akin to OS. hl[=u]d,
   D. luid, OHG. l[=u]t, G. laut, L. -clutus, in inclutus,
   inclitus, celebrated, renowned, cluere to be called, Gr.
   klyto`s heard, loud, famous, kly`ein to hear, Skr. [,c]ru.
   [root]41. Cf. Client, Listen, Slave a serf.]
   1. Having, making, or being a strong or great sound; noisy;
      striking the ear with great force; as, a loud cry; loud
      thunder.
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            They were instant with loud voices, requiring that
            he might be crucified.                --Luke xxiii.
                                                  23.
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   2. Clamorous; boisterous.
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            She is loud and stubborn.             --Prov. vii.
                                                  11.
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   3. Emphatic; impressive; urgent; as, a loud call for united
      effort. [Colloq.]
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   4. Ostentatious; likely to attract attention; gaudy; as, a
      loud style of dress; loud colors. [Slang]

   Syn: Noisy; boisterous; vociferous; clamorous; obstreperous;
        turbulent; blustering; vehement.
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