Description:

The term 'hun' and modifier 'hus' are a rare example of an irregular derivation between the term and modifier classes. This irregularity goes back to Old Common, and it is unknown what Davidson intended here, but modern grammarians treat them as a forms of the same word rather than two separate lexical entries, and consider the term form the lemma.

Term (Noun):

As a noun, 'hun' has an abstract meaning of 'similarity' (in more of a sense of being identical) or 'equality'.

Term (Verb):

As a verb, 'hun' is an intransitive pali verb that means 'equals' or 'be the same'. There are a number of ways it can be used:

With two or more absolutive arguments connected by 'epis' or with a plural or paucal absolutive argument. 'Hun' asserts the equality of its absolutive arguments. The focus is on the arguments equally. E.g.:

A cejátuin epis a cejítti se hun.
The man and (his) younger brother are the same.

Nar kawa pikki se hun.
The two cats are the same.

With any number of absolutive arguments in any number serving as the focus, and a paraphrastic argument introduced with 'wajy', in turn taking a nominative argument which is the comment or new information being introduced. It means the same thing as the former form but has a different rhetorical impact. E.g.:

A cejátuin se hun wajy na cejítti.
The man is the same as the (his) brother.

'Hun' can also take an optional argument introduced with the null preposition that is the manner in which the compared arguments are the same - the arguments compared can use any of the above structures. An adverb of manner can also be applied to hun directly to clarify the manner in which the arguments are the same. E,g,:

Nar kawa pikki se hun na lun.
The two cats are the same (of) the colour. (The two cats are the same colour)

Modifer:

The modifier form 'hus' means 'same' and typically clarifies that its term has the same identify as an earlier mentioned antecedent.

It can also be used specifically as a sentence level adverb that concerts a sense like 'even' or 'including'. Example: 

Hus xut zu nux kilum, zu nox ikky perat falu e na toly.

Even if you fly, you can't arrive on time. 

In colloquial speech, hus xut is enough of a set phrase that you often hear it blended together as something like 'huxxut' - it is very uncommon to see this expressed in writing unless trying to convey a feeling of informal dialogue.