when a female or females become obsessed with an older male or a group of older males.
typically seen in high school situations when an older guy will talk to a younger girl and despite any amount of ugliness/dickishness the girl will become obsessed and next to ignore or look down on guys of her own age.
girl: oh this guy in the year above talked to me the other day, he is perfect, despite how he is completely unfunny unattractive and an overall dick
guy: someone has older guy syndrome