Will Self

Just as the blurring between childhood and adulthood has produced the kidult, so the stretching of middle into old age has fostered another peculiar chimera: septuagenarians with apoptosis sporting the depeche mode.

English Author

Use 'septuagenarian' to be specific about someone's age being in the 70s, not just 'old'.

Age Precision

Often implies admiration for being active or healthy in one's seventies.

Positive Connotation

'Septuagenarian' is factual and neutral; it's not used to disrespect or belittle older individuals.