intransitive verb
: to have casual or illicit sex with a person or with many people
especially : to be sexually unfaithful to one's spouse
—usually used of a man
Etymology
from obsolete philander lover, philanderer, probably from the name Philander
[wiki says: name of the mythological son of the nymph Acacallis and the god Apollo.
In Greek mythology, Philander or Philandros (Ancient Greek: Φίλανδρος, meaning 'loving men') was the son of the nymph Acacallis and Apollo, and the brother of Phylacides. Their mother mated with the god in the house of Carmanor in the city of Tarrha. According to the Elyrians, Phylacides and Philander were suckled by a goat.]
First Known Use
1737, in the meaning defined above