The tatas (Greek: τατᾶς), more formally the tatas tes aules (Greek: τατᾶς τῆς αὐλῆς, lit. "tatas of the court") was a Byzantine court office attested in the 12th–14th centuries, whose exact functions are unclear.^[1]

The title is first attested in the seal of John Komnenos Vatatzes in the 12th century, and over the next two centuries.^[1] Nevertheless, the exact functions it entailed are unclear: according to the 14th-century historian Pachymeres, the tatas was one of the three major court functionaries along with the pinkernes (imperial cup-bearer) and the epi tes trapezes (master of the imperial table), but the 15th-century historian Doukas explains the title as "pedagogue". This led Ernst Stein to suggest that he succeeded the baioulos as imperial preceptor, a hypothesis rejected later by Vitalien Laurent.^[1]