That was my favorite non-word. It's great when you seem to have forgotten what you were supposed to say or when you just want to fill in the silence. This non-word is also very useful if you suddenly blanked out and cannot think of a word to say! Also, this could be very helpful if you unnecessarily blurted out a piece of information that you were not supposed to say in front of somebody - to help you backtrack a little bit and be able to think of a way to undo what you have just said. However, this non-word is also something I'm trying to take out of my repertoire of non-words. This could be so annoying especially if you're trying to interest people to listen to you (you know, it could be so redundant if your at the receiving end) or detrimental if you're trying to sound like english is your first language (when your working in a callcenter).
Ms. Bernie (my manager when I was still working as a trainer with SPPEI) already called my attention on this. Specifically when I took up the "Train the Trainers" course. Actually I have already discovered my affinity with this non-word even before I got my first job. To be honest, the English subject was never my favorite subject in school. Then there's the fact that in the school I attended (for both grade school and highschool) we even were using Filipino as the medium of teaching for almost all the subjects, of course except the english subject (duh!!!). I think they used us to be some sort-of of guinea pigs as to how it would affect our learning the subject matter. They even tried thinking of terms to be used in our chemistry, physics, algebra, geometry and trigonometry classes, but of course coming up with a filipino term for, let's say, vectors! That gave them the hint that they're proposal to use Filipino as the medium of teaching could be even detrimental to their students. I have strayed a little bit from my point - but that experience predisposed me to use this non-word because I was not able to practice and use the english language during the early stages of my life. I was not that comfortable when I speak english thus the tendency to say "uhmmm".
Ironically, I'm in a position right now that I absolutely have to speak the english language almost all the time. I work in a callcenter, we are the unfortunate ones whose task is to answer questions from customers who happens to be Americans. Great ain't it? So now, I'm slowly but surely removing that non-word. But of course, it occasionally still pops out of my mouth especially when I'm thinking of an excuse to make it seem like my company is not the one who made the error.