- 1〔一世代〕one [a] generation；〔一生〕one's lifetime
- a fortune built up in his lifetime
- the greatest mistake of one's life
- until a generation ago
- 2〔その時代〕the time; the day
- He was the greatest hero of his [the] day.
- 一代記a biography; a life
- 一代雑種the first filial hybrid