one who writes with his or her own hand, writes something him or herself (see Molina)
Orthographic Variants:
uelynoma tlacuilo
Alonso de Molina:
uelynoma tlacuilo. elque escriue algo desu propria mano. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 156r. col. 1. Thanks to Joe Campbell for providing the transcription.