When you see people from your past, you start acting like you did when you used to spend time with them. (i.e. you start acting like a 14-year-old when you unexpectedly run into your
freshman year boyfriend at the
grocery store)
As made popular by the character of Marshall Erikson on an April 2008 episode of CBS sitcom "How I Met
Your Mother".
When Linda, the 50-year old elegant
socialite, would squeal with delight,
bounce on her heels and speak in 70's youth-vernacular whenever she got together with her sorority sister Patty. Her husband
explained to his friend, "It's just Revertigo."