Muh What Does It Mean? Is It Mnh?

Australian sellers use MUH for their stamps.
What does it mean? Is there a difference with MNH?
Thank you

A British Commonwealth collector can give a better answer, but in the 1980's MUH meant that it did not currently have a hinge on the stamp. It did not not mean that it had never been hinged (MNH).

And now I saw that they use also UMM !
Where can I find the glossary of all those abbreviations?

UM or UMM is, I think, chiefly British. MUH is, I think, chiefly Antipodean.

UMM (unmounted mint) is most closely associated with sellers and collectors in Great Britain, however the term is still commonly used in philately in places like Australia, New Zealand, South Africa, etc. As more of these sellers became familiar with the style used on ebay by Americans and Canadians, they have gradually begun to use MNH exclusively, or concurrently with UMM.

I use a fairly large number of followed searches on ebay for stamps that have never been hinged, and to ensure I get as many hits as possible the searches look like this:

KGVI (mnh,nh,muh,nhm,umm,um,unmounted,never).... or..........

Nigeria (mnh,nh,muh,nhm,umm,um,unmounted,never)

The word "never" generally will capture titles with the words "mint never hinged" without grabbing all the "mint" and "hinged" listings I don't want to see.