The term 'Toughened Up' can be described by two crossword solutions: 'STEELED' (7 letters) and 'TEMPERED' (8 letters). Steeling is a process of hardening metal by heating it to a high temperature and then cooling it quickly. Tempering is a similar process, but involves heating the metal to a lower temperature and then cooling it slowly. Both processes are used to make metal more durable and resistant to damage.