toughened Synonyms

tough treated hardened tempered thick-skinned temper sturdy strong strengthen strengthened stiffen stiffened stiff make more severe toughening make stricter shatterproof nonbreaking galvanised hard-boiled case-hardened calloused reinforced tighten up armoured steeled solidified hard fortify fortified experient experienced callous braced bombproof armored annealed harden hardy indurated set seasoned rugged roughened resistant reinforce obdurate invigorated inured insensitive