[1] : The Collaborative International Dictionary of English v.0.48

undergird \un`dergird"\, v. t.
   to bind below; to gird round the bottom.
   1913 webster

         they used helps, undergirding the ship.  --acts xxvii.
                                                  17.
   1913 webster

[2] : WordNet (r) 2.0

undergird
     v 1: lend moral support to
     2: make secure underneath; "undergird the ship" syn: brace up
     also: undergirt
see also:
brace up undergirt 

[3] : Moby Thesaurus II by Grady Ward, 1.0

83 moby thesaurus words for "undergird":
   affirm, afford support, attest, authenticate, back, back up, bear,
   bear out, bear up, bed on, beef up, bolster, bolster up, bottom on,
   brace, brace up, build on, buoy up, buttress, carry, case harden,
   certify, circumstantiate, confirm, corroborate, cradle, crutch,
   cushion, document, finance, fortify, found on, fund, gird,
   give support, ground on, harden, hold, hold up, invigorate, keep,
   keep afloat, keep up, lend support, mainstay, maintain, nerve,
   pillow, probate, prop, prop up, prove, ratify, refresh, reinforce,
   reinvigorate, restrengthen, set on, shore, shore up, shoulder,
   stay, steel, stiffen, strengthen, subsidize, substantiate,
   subvention, subventionize, support, sustain, temper, toughen,
   underbrace, underlie, underpin, underset, upbear, uphold, upkeep,
   validate, verify, warrant

Undergird >> U Words
Undergird, definition of term: Undergird
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