pedantic (comparative more pedantic, superlative most pedantic)
Like a pedant, overly concerned with formal rules and trivial points of learning.
Being showy of one’s knowledge, often in a boring manner.
Being finicky or fastidious, especially with language.
(like a pedant): (informal, derogatory) anal-retentive, fussy, nit-picky
(knowledge-peacock): (sometimes applicable) nit-picky, ostentatious, pedagogical, pretentious
(linguistically affected): fussy, nit-picky
See also Thesaurus:fastidious