Does anybody know if labyrinths in classical times were mazes or labyrinths in the mathematical sense?

I'm not sure.

But maze comes from OE, labyrinth from the Greek. To the fussy-minded, this puts a Minotaur in the labyrinth, inextricably. But perhaps that labyrinth is both unicursal and infinite, or perhaps the time it takes the Minotaur to walk out of it exceeds the Minotaur's life span. In that case, the mathematicians' terminology squares with antiquity.