www.alphadictionary.com

Serendipity, one of my favorite words, led to this:

the middle-age period of life, especially when considered a difficult time of self-doubt and readjustment.

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A very new word, coined in the early 60s, could it serve as an enigmatic euphemism for the seven-year itch?

Not quite a second childhood, but an interesting concept nonetheless, no?

"Passages"was at one time a very popular book. It takes the developmental concept used often for children, and transfers it to adult life. It particularly became famous for its invention, or more likely popularizing, of the term midlife crisis. Roughly 5 years either side of 40 marks this period in which many affairs happen and/or people change jobs or even make major career shifts.

Very interesting word.