Floyd Mayweather -- I Never Said Ex was 'Drug Abuser' ... Just 'On Drugs'

Just because someone's "on drugs," doesn't mean they're a "drug abuser" -- so says Floyd Mayweather who claims his baby mama is making a drug mountain out of a drug molehill.

It all has to do with Floyd's $20 MILLION legal war with his ex Josie Harris -- who sued Floyd for defamation over comments he made about their domestic violence incident during an interview with Katie Couric.

In her lawsuit, Josie said Mayweather labeled her as a "drug abuser" who had to be restrained during the 2010 dom. violence incident.

But now, Mayweather is firing back -- saying he NEVER called Josie an "abuser" during the interview, just someone who was "on drugs" at the time of the incident. He insists there's a big difference.

For the record, Floyd was convicted of domestic violence and spent two months in jail for the attack -- and there was no mention of Josie being "on drugs" in any police report we've seen.