philanderer (n.)

1737, "pay court to women, especially without serious intent; flirt," from the noun meaning "a lover" (1700), from Philander, popular name for a lover in stories, drama, and poetry, from Greek adjective philandros "with love for people," perhaps mistaken as meaning "a loving man," from phil- "loving" (see philo-) + andr-, stem of anēr "man, male, husband" (see anthropo-). In later 20c. use more sexual than flirtatious. Related: Philandered; philandering.