It has been suggested that the "tennis" sense of love is derived from French l'œuf (the vowel in this French word has no English equivalent, but approximations would be something like "LERFF" or "LUFF"); œuf means "egg."
There are a number of theories relating to the origin of the word ‘love’ in tennis, but there are two which seem most commonplace. The first theory is that it the word ‘love’ compares to the French word l’oeuf, meaning ‘an egg’. This is due to the fact that the oval shape of the egg is somewhat comparable to the number zero, or a nought (0).
Origin of the Term Love in Tennis. While the origin of the term “love” in tennis remains a bit of a mystery, there are two commonly shared ideas. The first, and less likely, would be that the term love is an adaptation of the French word l’oeuf, which translates to egg or the shape of a 0.
The origins of the game today are traced to a 12th–13th-century French handball game called jeu de paume (game of the palm). Since then, the game has evolved into what we love to watch and play today. There are two main theories as to where the term love comes. L’oeuf means egg in French, and because an egg looks like a zero, some tennis historians believe that is where the term came from.
This theory reflects the sport’s long history of etiquette and sportsmanship. Others theorize that love arose from the French word for “egg,” l’oeuf, because a zero on a scoreboard resembles an egg. This is a clever claim, but it remains unsubstantiated. Tennis might have ended up with a different name altogether.
Sometimes there is anything but love on a tennis court especially in the heat of a battle, so why did this word come into the game of tennis? According to etymologists, the word love is possibly derived from the French word l’oeuf which literally means egg.
Many of the words used in Tennis today came from French Language. The word Love (for zero score) comes from French word l'oeuf - which means egg which is the shape of zero. The word Tennis itself originated from the French word tenez - which means to receive.
Deuce comes from à deux le jeu, meaning "to both is the game" (that is, the two players have equal scores). The origin of the use of love for zero is disputed. It is ascribed to derive from l'œuf, French for "the egg", traditionally representing the shape of a zero.