From the ancient history of the internets, and usenet in particular, a meower was an early sort of organized troll. Basically, meowers were a group of usenet trolls who congregated in the newsfroup alt.fan.karl-malden.nose. There, they would organize raids on other, unsuspecting newsgroups, descending upon them in droves, and flooding the group with 'meow' messages or cascades, thus rapidly rendering their target completely unusable.

A cat, domestic or wild, however typically domestic.

Can be used as a substitute for many vulgar words such as fucker or non-vulgar words such as loser.

ORIGIN: One day, I happened to start meowing, and then I started calling people meowers. The end.

Miss Meower. To Strut your stuff down the sidewalk. Typically, a meower only qualifies if she is physically hot and mentally smart. Damn she is a total meower.

A girl who meows during actual conversation or through text/IM messages

Most likely has an obsession with cats and becomes overly excited when discussing cats

May not meow until she is totally comfortable with the people she's around

According to the Meow Law she is most likely crazy and good in bed

Me·ow·er·s
A large man cat that meows wearing cat ears and bouncing around, sometimes if over stimulated, he is found to bite people at music festivals.
His female counter part is a bully, attractive, usually blonde or pastel haired female that at times is mistaken for a unicorn.

Cat that acts like a dog