without an owner, a stray (a metaphor) (see Molina)
Alonso de Molina:
xomulco caltech nemini. mostrenco. metaphora. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 161r. col. 1. Thanks to Joe Campbell for providing the transcription.