To describe an old warrior or experienced person who, despite their age, remains full of vigor, ambition, and readiness for action; an old warhorse still ready for battle.
Era:
Ancient
Frequency:
Story:
During the early Eastern Han Dynasty, when the domestic situation was still unstable and ethnic minorities in the northwest rebelled, the 62-year-old general Ma Yuan requested to lead an expedition. Emperor Guangwu of Han, Liu Xiu, initially denied his request, deeming him too old.
Ma Yuan insisted he could still don armor and mount a horse, and then personally demonstrated his undiminished prowess. Emperor Guangwu was greatly pleased by this display, praising him for being 'an old sword that's not dulled' (meaning 'still sharp and capable'), and allowed him to lead the troops into battle.