Synonyms to youthen

rejuvenate, bring back, bring to, call back, modernize, reanimate, recall to life, recharge, reclaim, recondition, reconstruct, recover, recruit, refresh, refurbish, regenerate, rehabilitate, reheat the ashes, reinspire, reinvigorate, rekindle, relight, renew, renovate, restitute, restore, resurrect, resuscitate, revitalize, revive, revivify, rewarm, stir the embers, update, warm over, warm up