what would the part of speech be for the word ugh in the sentence

ugh, i am tired of this

It's an interjection!

The word "ugh" in the sentence "ugh, I am tired of this" is an interjection.

To determine the part of speech of a word, you can consider its function in the sentence and its role in conveying meaning. Interjections are words or phrases that express strong emotions or reactions and are not grammatically related to the rest of the sentence. In this case, "ugh" is an expression of frustration or disgust, indicating the speaker's feelings towards the situation.