τὸν αὐτὸν ἔρανον ἀποδοῦναι → pay him back in his own coin, repay him in his own coin, pay someone back in their own coin, pay back in someone's own coin, give tit for tat, pay back in kind
pēro: ōnis, m.,
I a kind of boot made of raw hide, worn chiefly by soldiers and wagoners (cf. caliga): crudus, Verg. A. 7, 690: alto per glaciem perone tegi, Juv. 14, 186; App. M. 7, p. 465; Sid. Ep. 4, 20: perones effeminati, Tert. Pall. 5.