nit-picking

Noun

nitpicking (countable and uncountable, plural nitpickings)

1. The painstaking process of removing nits (lice eggs) from someone's hair.
2. (broadly, figuratively) A process of finding or pointing out tiny details or errors, particularly if the pointed-out details seem insignificant or irrelevant to all but the finder.
   • "Of all life's pleasures, I like nitpicking the best." -- Wally in Dilbert