Paddy-waggler

A person incapable of holding intelligent conversation, normally seen in a business meeting scenario where any sound or word uttered is met with disbelief from his/her colleagues as it does not normally pertain to the subject of the meeting.

Meeting attendee: "I wanted to mow my lawn on Sunday but my grass was too short"
Chairman of meeting, muttering under his breath "for god's sake, he's such a paddy-waggler"