I'm not middle aged but I have heard this term before Infact there's even a song about this phenomenon from 1992 called mid life crisis. So what exactly is a mid life crisis and how does one identity one ?
The joke is that a midlife crisis is when a Jewish man gets a hair toupee, buys a Maserati, and drives around town with his Shiksa goddess of love.
On a more serious note, a midlife crisis is when a man (usually between 40 and 60 years old) develops feelings of dissatisfaction, anxiety, or confusion about his life, accomplishments, and future direction. He will begin questioning his identity, career, relationships, and other life choices. This leads to significant and impulsive changes, such as quitting his job, or leaving his wife and children for a hot babe.