fact of life

American  

noun

1. any aspect of human existence that must be acknowledged or regarded as unalterable.

   Old age is a fact of life.

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idioms

1. facts of life,  the facts concerning sex, reproduction, and birth.

   to teach children the facts of life.

Etymology

Origin of fact of life

First recorded in 1850–55

Example Sentences

At virtually every taxpayer-funded institution in Texas that teaches anything about medicine, DEI is still a fact of life.

From The Wall Street Journal

Neither seems to notice that the most astonishing, extraordinary fact of life is our existence.

From The Wall Street Journal

Beyond that, he also believes that he can usher in new ways of living, in which performance-enhancement isn’t reserved for elite athletes, but becomes a daily fact of life.

From The Wall Street Journal

With the ongoing shutdown of the federal government, travelers are starting to find that flight delays and cancellations are becoming a fact of life.

From MarketWatch

Another traveller, Paul Weallans, described the strikes as "a fact of life in London" and hoped a resolution would "not be a long time coming".

From BBC