Coed is short for coeducational. This means, both men and women can play on the same team.
Coeducation is the integrated education of men and women at the same school facilities; co-ed is a shortened adjectival form of co-educational.

"Coed" is an informal (and increasingly archaic) term for a female student attending such a college or university. Before the 1960's, most institutions of higher education restricted their enrollment to a single sex.

A person or people that purposefully causes chaos or mischief within a group for the sake of entertainment.

In 50-60s it was a slang word, meaning any woman who was a student on a predominantly male campus.

The term is almost not used except for in association with porn, it allows someone searching for porn to use a search term that would more likely produce a porn specific result.

For example compare the search results for “cute college girl” vs “cute coed”

A place or situation that is open to both male and female sexes.

The slutty, young babes most likely to appear on any "Girls Gone Wild" porn video.

Bisexual, threesomes, Group, Open-sexuality, orgy, men and women,

when someone is being a bitch or lame