Animadverter is a rarely used word that refers to a person who offers critical comments. Some synonyms for animadverter include critic, censurer, faultfinder, and disapprover. Other synonyms include detractor, fault-finder, judge, and blamer. A person who is quick to point out flaws and criticize can also be called a nitpicker, fault-picker, or carper. However, it's important to note that criticism isn't always negative. Constructive feedback can help individuals improve and grow. Therefore, synonyms such as evaluator, assessor, and appraiser may be more appropriate if the person offering the critical feedback has good intentions and is trying to help.