seventieth

All the septuagenarians remembered their seventieths fondly.

Tom died just one day after his seventieth birthday.

My father celebrated his seventieth birthday this year, but he's more energetic than I am.

Tom passed away in the seventieth year of his life.

Tom died in his seventieth year.

It took him four attempts over several years, but in nineteen eighty-five, he became the two hundred and seventieth person to swim across the Channel.