Meliodas is the name of Tristan’s father of Tristan and Isolde fame, though in some versions his father is Rivalen. There’s not a lot I could find about the name’s meaning, though it was used for the main character in a manga called The Seven Deadly Sins (Nanatsu no Taizai in Japanese) which seems to be a blend of Arthurian legend, Christianity, and medieval folklore. If I had to take a guess, I would say that the first part of the name comes from Latin mel (honey) from Greek meli (honey) and Late Latin oda derived from Ancient Greek ōidḗ, a contracted form of aoidḗ meaning “song, ode” so the name could essentially meaning “sweet song” or “honey song”. Of course, the name could also be the masculine form of Melodia, also derived from Ancient Greek meaning “singing, chanting” from melos (song, melody) and aeídō (to sing, chant, praise). However, that’s just my guess. Since the stories of Arthurian legend were very popular, especially during medieval times and since there seems to be historical facts and figures mixed in with the legends, and it’s been written and rewritten by both English and French writers, it’s possible Meliodas was influenced by Latin and Greek although, once again, that’s purely my guess.
Origin: Ancient Greek