Greens' Upper House Member Jeremy Buckingham said all reasonable people find Mr Trump obnoxious. He has also denied touching women inappropriately.
United States talkshow host Rosie O'Donnell had previously described Trump as "an orange slug".
The only uncertainty came when President of the Legislative Council Don Harwin paused to check whether "revolting slug" was unparliamentary language, the Sydney Morning Heraldreports. Parliamentary procedure prevents MPs from using "extremely distasteful" words.
Trump's campaign - controversial from its start - hit a new low on Saturday after the Washington Post unearthed tapes of the Republican candidate from 2005 boasting about how he could kiss and grope women without their consent.
Australians heard about Donald Trump's video scandal, and they're not happy. "Why bother for a revolting slug overseas, try looking at our own backyard. And slugs is quite generous to describe them", said Katherine Fav. He previously "vaped" an e-cigarette in parliament and set a river in Queensland on fire.