great achievement; great feat; great work
Refers to a remarkable accomplishment, often in fields like science, sports, or history. Carries a formal, respectful tone.
He accomplished a great feat that became the world's first of its kind.
His Nobel Prize win is a great achievement in the scientific world.
この橋の建設は当時としては偉業だった。
The construction of this bridge was a great feat at the time.
This athlete established an unprecedented great feat.
The scientist left behind an achievement that remains in human history.
She became the first woman to achieve an unprecedented feat.
快挙 highlights a thrilling, admirable feat often achieved against odds, whereas 偉業 focuses on the monumental or historically significant nature of the achievement.
業績 refers broadly to one's accumulated work or output (e.g. in research or business), while 偉業 singles out one truly great, standout feat.
遺業 (same reading いぎょう) means the unfinished work or legacy left behind by someone who has died, whereas 偉業 means a great accomplishment itself, with no implication of death.
Compound of 偉 (great, admirable) and 業 (work, deed). The kanji combination directly conveys 'great work'.