A person with no experience in software development that read a few books on Agile development and is acting like an expert.

A person that is not being a team player in a Scrum meeting. (Agile Product Development Reference)

a scrub and a scumbag at the same time

A member of a scrumteam (agile application development)

A step above a scumbag: a person whom you once regarded highly but upon spending more time with them, you find that person demonstrates questionable habits, morals, or ethics.