Guinefort

This is the name of a 13th-century dog (specifically a greyhound) from near the city of Lyon in southeastern France, which at the time was part of the Holy Roman Empire. He lost his life after successfully protecting an infant from a snake, after which people began to venerate him as a patron saint of infants. The Church did not approve of this and made great efforts to eradicate the practice, but ultimately failed: the cult of this canine saint managed to persist until the early 20th century.

The name Guinefort might be a simpler form of Guignefort, which the saint was also known by. This indicates that the first element of the name consists of the Old French verb guignier meaning "to signal" (as in, to make a sign to someone). A descendant of this word is guigner meaning "to wink" as well as "to eye someone", which is related to the superstition of the evil eye.

However, it is also possible that the first element actually comes from Old German wini meaning "friend", as names with that element typically become Guin- in French (with Guign- as an alternative spelling).

Finally, the second element of the name should be derived from the Old French adjective fort meaning "strong".