As with most rock songs, speculation ensued among fans as to the meaning of the lyrics, particularly over exactly to whom the song's character of "the Seether" refers. The song "Volcano Girls," does include the line, "The Seether's Louise" (i.e. Veruca Salt vocalist Louise Post), however, this could be in jest. This was borrowed from "The Beatles" song "Glass Onion" in which the identity of The Walrus is sung as "The Walrus was Paul."
According to an unofficial Veruca Salt FAQ (http://www.chrispy.net/~cheeks/FAQ.html), "Nina Gordon wrote Seether after having a discussion with someone and disagreeing so violently that she wanted to bash her face in. Simply put, Seether is about anger, a seething anger, hence the name. It has been said that it's more about a woman's anger, the kind of anger 'a woman is not supposed to show.'"
According to Shaun Morgan of the band Seether, the word "seether" is allegedly used in the UK to refer to a vagina. It is from this song that the band Seether got their name, and they use an X-ray diagram of a woman's reproductive system as a logo for T-shirts and merchandise.