Yours is an almost archaic definition of the word, 'slut'.
Simply having pre-marital sex doesn't qualify anyone for 'slut' status in the minds of most people. You'd have to go back 150 years for that to be the common agreement.
Today, a slut is (always) a woman of extremely loose sexual mores. The type who 'sleeps around' with anyone she so chooses, and any time she so chooses. Basically, a whore. Not someone who loses their virginity to their high school or college sweetheart.
The reason people are so upset about what Rush said, is because the term carries such a negative connotation today.
I am archaic in all respects and most certainly do not claim to speak for ‘most people’. My definitions of right and wrong in morality are absolute and unchanging. By coincidence, perhaps, so are God’s.
Although ‘slut’ does typically carry a connotation of promiscuity, in my religion (traditional form) pre-marital and adulterous sex are considered mortal sins and would result in loss of soul if not forgiven. Even if it circumstances involve loss of virginity “to their high school or college sweetheart”. That’s good enough to earn the designation of slut (or male counterpart) in my lexicon.