A play on the word "hungover."
When one comes home after doing something extremely fun, such as going on vacation or having an adventure, and is simply unable to function as a productive
human being in the aftermath of such frivolousness.
Symptoms include lounging about, not
getting any work done, wishing to go back to having fun, plotting to skip work/school
the next day, antisocial behavior, and poor hygiene.
A funover may last between one day and a week, though residual symptoms may continue for up to months afterwards if daily stress levels are high.