Fellow

Being part of any professional or academic society, we get to hear the word 'fellow' quite often. And whenever we hear it, we attribute it to the noteworthy tasks the person has done to the field / group or the adjoining body.
Recently, during a chat with a few of my office colleagues, I started to hear another usage of the word.

"This is the fellow who is responsible for the work."

"Why did this fellow not tell us what is happening?"

I found the usage quite annoying - wherein the word denoted a person who was not particularly positive in the work he /she did. I'm not certain how the colleague got to use the word 'fellow' when trying to mention a person in a negative way.
Once again, this is more of a funnier situation when you have the real Fellows who have done things on a large scale significance to the field and on the contrasting side, there are the conversational fellows who are pulled in when they didn't do their jobs properly!!!