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

fortify \for"tify\, v. t. imp.  p. p. fortified; p. pr. 
   vb. n. fortifying. f. fortifier, l. fortificare; fortis
   strong + -ficare in comp. to make. see fort, and -fy.
   1. to add strength to; to strengthen; to confirm; to furnish
      with power to resist attack.
      1913 webster

            timidity was fortified by pride.      --gibbon.
      1913 webster

            pride came to the aid of fancy, and both combined to
            fortify his resolution.               --sir w.
                                                  scott.
      1913 webster

   2. to strengthen and secure by forts or batteries, or by
      surrounding with a wall or ditch or other military works;
      to render defensible against an attack by hostile forces.
      1913 webster
see also:
fortified fortifying fort -fy 

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

fortify \for"tify\, v. i.
   to raise defensive works. --milton.
   1913 webster

[3] : WordNet (r) 2.0

fortify
     v 1: make strong or stronger; "this exercise will strengthen your
          upper body"; "strenghten the relations between the two
          countries" syn: strengthen, beef up ant: weaken
     2: enclose by or as if by a fortification syn: fort
     3: prepare oneself for a military confrontation; "the u.s. is
        girding for a conflict in the middle east"; "troops are
        building up on the iraqui border" syn: arm, build up,
         gird ant: disarm
     4: add nutrients to; "fortified milk"
     5: add alcohol beverages syn: spike, lace
     also: fortified
see also:
strengthen beef up weaken fort arm build up 
gird disarm spike lace fortified 

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

126 moby thesaurus words for "fortify":
   add to, adulterate, affirm, animate, arm, armor, armor-plate,
   arouse, attest, augment, authenticate, back, back up, bank,
   barricade, bastardize, battle, bear out, beef up, blockade,
   bolster, boost, brace, brace up, brisk, brisken, buck up, bulwark,
   buoy, buttress, case harden, castellate, certify, cheer, chirk up,
   circumstantiate, confirm, contaminate, corroborate, corrupt,
   crenellate, cut, debase, denaturalize, denature, dig in, dilute,
   doctor, doctor up, document, embattle, embolden, encourage,
   energize, enhance, enliven, enrich, entrench, exhilarate, fence,
   fresh up, freshen, freshen up, garrison, gird, harden, hearten,
   increase, invigorate, lace, man, man the garrison, mine, nerve,
   palisade, perk up, pick up, pollute, prepare, probate, prop, prove,
   quicken, rally, ratify, ready, reanimate, reassure, recreate,
   recruit, refresh, refreshen, regale, reinforce, reinvigorate,
   renew, restore, restrengthen, revive, revivify, rouse, secure,
   set up, shore up, spike, steel, stiffen, stimulate, stir,
   strengthen, substantiate, supplement, support, sustain,
   tamper with, temper, toughen, undergird, uphold, validate, verify,
   vivify, wall, warrant, water, water down

Fortify >> F Words
Fortify, definition of term: Fortify
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