pedant
definition
a person who is excessively concerned with minor details and rules or with displaying academic learning
example
As a pedant, she spent hours correcting minor punctuation errors in her friend's thesis instead of focusing on the overall argument.
synonyms
nitpickerdogmatistformalist
word origin — From French 'pédant' meaning 'a teacher,' from 'pédante' meaning 'learning' or 'to teach,' derived from the Latin 'paedagogans' meaning 'to lead a child.'