Beth Chapman is learning the hard way ... you don't call another chick a whore and a slut in Colorado ... because she's now facing imminent arrest.

Beth and hubby Dog the Bounty Hunter were fishing at a lake earlier this month when a car roared by ... which didn't sit well with the famous couple and their kids. Beth allegedly began berating the teenage passenger, whom she called a tramp, a whore and a slut, among other choice words.

The situation escalated ... and Beth called 911, claiming one of the people in the party she confronted was ominously carrying a gun with his hand on the grip.

By the time cops arrived, Beth and her brood had split. But the teen filed a criminal harassment complaint. Under Colorado law, if someone taunts, challenges or uses "coarse language" against someone, it's a crime. It appears slut and whore qualify.

So cops issued a summons for Beth to appear in court on the misdemeanor harassment charge. Law enforcement tells TMZ ... they called her on her cell several times to come down to the station to pick up the summons, but she blew them off.

So police issued an arrest warrant, which means Dog could make some money by cuffing his wife and taking her to the station -- kidding.

Cops tell us ... Beth's lawyer has already contacted them, and arranged for Beth to turn herself in and accept the summons.