You can, and probably 99% of trademarked brands are dictionary words, but not when the word means generically what your product does and you try to use just that word as your mark. You can't trademark "Computer", but you can trademark "Apple Computer" or "Dell Computer", etc.
Telepresence is a recently made-up word, so it's plausible that one could register it as a mark...but defending the mark would be difficult.