The Collaborative International Dictionary of English v.0.48:

Sound \Sound\, v. t. [imp. & p. p. Sounded; p. pr. & vb. n.
   Sounding.] [F. sonder; cf. AS. sundgyrd a sounding rod,
   sundline a sounding line (see Sound a narrow passage of
   water).]
   1. To measure the depth of; to fathom; especially, to
      ascertain the depth of by means of a line and plummet.
      [1913 Webster]

   2. Fig.: To ascertain, or try to ascertain, the thoughts,
      motives, and purposes of (a person); to examine; to try;
      to test; to probe.
      [1913 Webster]

            I was in jest,
            And by that offer meant to sound your breast.
                                                  --Dryden.
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            I've sounded my Numidians man by man. --Addison.
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   3. (Med.) To explore, as the bladder or urethra, with a
      sound; to examine with a sound; also, to examine by
      auscultation or percussion; as, to sound a patient.
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The Collaborative International Dictionary of English v.0.48:

Sounding \Sound"ing\, a.
   Making or emitting sound; hence, sonorous; as, sounding
   words. --Dryden.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sounding \Sound"ing\, n.
   1. The act of one who, or that which, sounds (in any of the
      senses of the several verbs).
      [1913 Webster]

   2. (Naut.) [From Sound to fathom.]
      (a) measurement by sounding; also, the depth so
          ascertained.
      (b) Any place or part of the ocean, or other water, where
          a sounding line will reach the bottom; -- usually in
          the plural.
      (c) The sand, shells, or the like, that are brought up by
          the sounding lead when it has touched bottom.
          [1913 Webster]

   Sounding lead, the plummet at the end of a sounding line.


   Sounding line, a line having a plummet at the end, used in
      making soundings.

   Sounding post (Mus.), a small post in a violin,
      violoncello, or similar instrument, set under the bridge
      as a support, for propagating the sounds to the body of
      the instrument; -- called also sound post.

   Sounding rod (Naut.), a rod used to ascertain the depth of
      water in a ship's hold.

   In soundings, within the eighty-fathom line. --Ham. Nav.
      Encyc.
      [1913 Webster]

WordNet (r) 3.0 (2006):

sounding
    adj 1: appearing to be as specified; usually used as combining
           forms; "left their clothes dirty looking"; "a most
           disagreeable looking character"; "angry-looking";
           "liquid-looking"; "severe-looking policemen on noble
           horses"; "fine-sounding phrases"; "taken in by high-
           sounding talk" [syn: looking, sounding]
    2: having volume or deepness; "sounding brass and a tinkling
       cymbal"; "the sounding cataract haunted me like a passion"-
       Wordsworth
    3: making or having a sound as specified; used as a combining
       form; "harsh-sounding"
    n 1: a measure of the depth of water taken with a sounding line
    2: the act of measuring depth of water (usually with a sounding
       line)

Moby Thesaurus II by Grady Ward, 1.0:

49 Moby Thesaurus words for "sounding":
   bathometry, bathymetry, booming, chiming, depth sounding, dinging,
   droning, echo sounding, echoic, echoing, echolocation, fathomage,
   fathoming, growling, jingling, lingering, monotone, monotonic,
   oceanography, pealing, persistent, reboant, rebounding, reechoing,
   repercussive, resounding, reverberant, reverberating,
   reverberatory, ringing, rumbling, sonar, sonation, soniferous,
   sonification, sonorous, sounded, soundings, thundering, tingling,
   tinkling, tintinnabular, tintinnabulary, tintinnabulous, tolling,
   tonal, toneless, undamped, water