Mystified by This Crossword Clue? Discover the Answer!

Mystified by This Crossword Clue? Discover the Answer! - UHH
[I'm thinking …]

Three letters
A sound made when hesitating or unsure
Commonly used in speech
Often used as a filler word
Starts with the letter “U”
Ends with the letter “H”
No vowels present in the answer
Can be spelled with a single letter when written phonetically

UHH