"Welcome to YouX," the organisation's Facebook page wrote on Monday.
"As a student services provider, our main priority is your student experience, and our new name helps us put you at the heart of our brand."
When the AUU changed its Facebook profile to YouX last week, comments were overwhelmingly negative, with people blasting the rebrand as "embarrassing" and "horrendous".
"When you can't be called a union because then people might expect you to defend their rights," one person wrote.
Another said, "What is this nonsense? My God the uni is a shell of what it was if the AUU couldn't handle being called a union. Where is the common sense?! I thought the page had been hacked and I was ready to delete it. It looks like a bot took over! You can't completely change a name to some weird dystopian 'meta' name to appease tossers. Union and proud!"
A third wrote, "Right wingers will literally spend ??? amounts on a rebrand nobody wanted instead of being a union for the students."
A fourth added, "Imagine being a university union for over 125 years and then having the name changed coz some goons are a bit frightened of the word union. Well done chums."
One said it "looks and sounds like a consulting company", while another said it "sounds like a cult".
"I genuinely had to stalk through your page to find out that this is a student union rebrand," another wrote. "Assumed it was some MLM [multi-level marketing] takeover of a FB page."
The AUU board had also been accused of stripping power from the Student Representative Council earlier this year. The SRC said it was "deeply concerned" about the rebrand.
"We believe that there has been a lack of genuine student consultation with AUU members on this rebrand as well as potentially an unjustifiably high price tag," it said in May.
"We are worried that this rebrand has political intentions and is only being proceeded with due to the desire from figures on the AUU Board to remove the world 'union'."
Last week, On Dit wrote that despite denials that the name change was politically motivated, "politics and massive political implications cannot be separated from discarding the profound and historic word, union".
"The removal of the word union is a woeful defeat for all students and staff at the university," the paper wrote.
"Yes, whilst certain essential services remain, students are left without the knowledge and ease of taking matters into their own hands through united power. Students, especially future students are facing the risk of losing their power for self-determination and for their ability to fight."
A YouX spokesman told the Adelaide Advertiser feedback to the rebrand "so far has been overwhelmingly positive".
"We have not been made aware of any instances where students have encountered inappropriate content using our name as a search phrase, and all testing to date has produced no unsafe search returns," he said.
"Indexing of new sites can take time [up to a week] and in the interim search results may be mixed but once completed we believe searching and finding YouX will be easy and user-friendly."
The spokesman would not reveal the cost of the rebrand due to "commercial in confidence" issues, but said it had been funded through profits from "commercial entities", not student services fees.
YouX has been contacted for further comment.
