pedantic adj.

1580s, "schoolmaster," from French pédant (1560s) or directly from Italian pedante, literally "teacher, schoolmaster," a word of uncertain origin, apparently an alteration of Late Latin paedagogantem (nominative paedagogans), present participle of paedagogare (see pedagogue). Meaning "person who trumpets minor points of learning, one who overrates learning or lays undue stress on exact knowledge of details or trifles as compared with large matters or general principles" is recorded by 1590s.

Middle English -ik, -ick, word-forming element making adjectives, "having to do with, having the nature of, being, made of, caused by, similar to," from French -ique and directly from Latin -icus or from cognate Greek -ikos "in the manner of; pertaining to." From PIE adjective suffix *-(i)ko, which also yielded Slavic -isku, adjectival suffix indicating origin, the source of the -sky (Russian -skii) in many surnames. In chemistry, indicating a higher valence than names in -ous (first in benzoic, 1791).

In Middle English and after often spelled -ick, -ike, -ique. Variant forms in -ick (critick, ethick) were common in early Modern English and survived in English dictionaries into early 19c. This spelling was supported by Johnson but opposed by Webster, who prevailed.

"a pedantic notion or expression," by 1836, from pedantic + -ism. Earlier was pedantism (1590s) "the character or style of a pedant."