Lewis Short
grammătista (noun M) = γραμματιστής:
* A teacher of grammar or of languages: sunt qui litteratum a litteratore distinguant, ut Graeci grammaticum a grammatista: et illum quidem absolute, hunc mediocriter doctum existiment,Suet. Gramm. 4; id. ib. 24; Mart. Cap. 3, § 229.
Charlton T. Lewis, Charles Short, A Latin Dictionary