The victim in the Lindsay Lohan nightclub fight tells TMZ ... Lohan hurled a racial slur at her moments before the brawl ... calling her a "f**king Gypsy."
TMZ spoke with Tiffany Mitchell -- a well-known psychic who was at the club Avenue with a friend Wednesday night when Lohan walked in.
Tiffany tells us ... she had a premonition about Lohan and approached her inside the club to offer her a free reading ... but Lohan turned her down saying, "Give me my space."
As she walked away, Tiffany's friend says she heard Lohan call her a "f**king Gypsy" ... and it set her off.
We're told the friend went ballistic -- unloading a bunch of insults back at Lohan ... calling her a "whore" and telling her "Liz & Dick sucked."
At that point, Lohan lost her cool and socked the psychic in the eye ... and all hell broke loose inside the club. Lohan was eventually arrested for assault.
Tiffany's husband tells TMZ, "We are not Gypsies. That has nothing to do with our religion ... it was a racist comment."
He adds, "Just because your career went down the drain and your new movie sucks, you can't go around beating people up."
As for the connection to Max from "The Wanted" -- we're told Tiffany DID have a convo with the heartthrob earlier in the evening ... but it was just a friendly conversation and Lindsay had nothing to be jealous about.