Panther
Middle English: from Old French pantere, from Latin panthera, from Greek panthēr . In Latin, pardus ‘leopard’ also existed; the two terms led to confusion: until the mid 19th century many taxonomists regarded the panther and the leopard as separate species.
wiktionary
From Middle English panter, panther, pantere, from Old French pantere, from Latin panthera, from Ancient Greek πάνθηρ(pánthēr, “panther”), perhaps related to Sanskrit पुण्डरीक(puṇḍárīka, “tiger”).
etymonline
panther (n.)
mid-13c., panter, another name for the leopard, from Old French pantere "panther" (12c.) and directly from Latin panthera, from Greek panther "panther, leopard," probably of Oriental origin. An ancient folk-etymology derivation from Greek pan- "all" + thēr "beast" led to many curious fables. The word was applied to the American cougar or puma by 1730.
