strengthen

1 to increase the ability of (as a muscle) to exert physical force <lifting weights every day will eventually strengthen your muscles> <the army makes new recruits run for miles in order to strengthen them> Synonyms beef (up), fortify, harden, toughen Related Words anneal, temper; firm (up), tone (up); energize, invigorate, vitalize; restrengthen Near Antonyms cripple, incapacitate, paralyze; damage, harm, hurt, impair, injure; break down, wear out; sap, undercut, undermine Antonyms debilitate, enervate, enfeeble, weaken

2 to make able to withstand physical hardship, strain, or exposure <required weeks of physical therapy to strengthen his arm enough to pitch for the team again> Synonyms fortify, indurate, inure, season, steel, harden, toughenRelated Words acclimate, acclimatize, adapt, adjust; anneal, temper; invigorate, vitalize; immunize; bolster, boost, brace, buttress, enforce, forearm, prop (up), reinforce (also reenforce), support; break in, limber (up), train; accustom, condition, habituate, naturalizeNear Antonyms emasculate, enervate, enfeeble, exhaust, sap, weaken; cripple, debilitate, hamstring, incapacitate; sensitizeAntonyms soften

3 to make markedly greater in measure or degree <encouraged the boarding school students to strengthen their ties with the community by doing public service> Synonyms accentuate, amp (up), amplify, beef (up), boost, consolidate, deepen, enhance, heighten, magnify, redouble, step up, intensifyRelated Words broaden, enlarge, expand, extend, lengthen; accelerate, hasten, quicken; emphasize, point (up), sharpen, stress; augment, enforce, reinforce (also reenforce), restrengthen, supplement; maximize; enliven, jazz (up); aggravate, exacerbateNear Antonyms decrease, diminish, lessen, let up (on), reduce, subdue, tone (down), weaken; dwindle, recede, subside, taper (off), wane; alleviate, ease, lightenAntonyms abate, moderate

4 to prepare (oneself) mentally or emotionally <strengthened herself for the moment she'd have to tell her friend that she had lost the borrowed necklace> Synonyms brace, forearm, nerve, poise, psych (up), ready, steel, fortifyRelated Words arm; harden, inure, season, toughen; bolster, boost, buoy (up), buttress, enforce, prop (up), reinforce (also reenforce), support, sustain; cheer (up), comfort, embolden, encourage, hearten, inspire; rally, rouse, stirNear Antonyms daunt, demoralize, discourage, dishearten, dispirit, psych (out), shake, unnerve; debilitate, enervate, enfeeble, prostrate, sap, soften, tire, undercut, undermine, weaken

5 to make more harsh, uncompromising, or severe <a bill was introduced to strengthen punishments for hate crimes> Synonyms harden, stiffen, harshen, toughenNear Antonyms lessen, moderate, softenAntonyms ameliorate, ease