Grammaticus

Grammaticus is the Latin word for grammarian; see Grammarian (Greco-Roman world). It is also used to refer to a Roman patrician school.

As an agnomen, it may refer to:
 * Ammonius Grammaticus (4th century), Greek grammarian
 * Diomedes Grammaticus (4th century), Latin grammarian
 * Musaeus Grammaticus (6th century), Greek poet
 * Virgilius Maro Grammaticus (7th century), early medieval Latin writer
 * John VII of Constantinople, known as John VII Grammaticus (9th century), Ecumenical Patriarch of Constantinople
 * Ælfric of Eynsham, known in Latin as Alfricus Grammaticus (10th century), Anglo-Saxon abbot and author
 * Saxo Grammaticus (circa 1150 – 1220), Danish medieval historian

As a pseudonym:
 * Edward Musgrave Blaiklock, (1903–1983), British born New Zealand author, wrote as "Grammaticus"