backseat driver β If you refer to a passenger in a car as a backseat driver, they annoy you because they constantly give you advice about how to drive.
be-little β to regard or portray as less impressive or important than appearances indicate; depreciate; disparage.
blame β If you blame a person or thing for something bad, you believe or say that they are responsible for it or that they caused it.
censurer β strong or vehement expression of disapproval: The newspapers were unanimous in their censure of the tax proposal.
fretter β to feel or express worry, annoyance, discontent, or the like: Fretting about the lost ring isn't going to help.
hypercritic β a person who is excessively or captiously critical.
pan β an international distress signal used by shore stations to inform a ship, aircraft, etc., of something vital to its safety or to the safety of one of its passengers.
reviler β to assail with contemptuous or opprobrious language; address or speak of abusively.
sidewalk superintendent β a bystander who watches the building, demolition, repair, or other work being done at a construction site.
critic β A critic is a person who writes about and expresses opinions about things such as books, films, music, or art.
nitpicker β a person who nitpicks, especially habitually.
niggler β to criticize, especially constantly or repeatedly, in a peevish or petty way; carp: to niggle about the fine points of interpretation; preferring to niggle rather than take steps to correct a situation.