French and Spanish nouns often have the same gender. This is not surprising because they are both Romance languages that are descended from Latin. This is the case with the French phrase le livre and the Spanish phrase el libro with the meaning "the book." Both phrases have masculine gender. The French phrase la lune and the Spanish phrase la luna mean "the moon." In this case they share feminine gender. However, a number of related nouns do not share the same gender.
Here is a list of ten nouns with different genders in French and Spanish:
le sang la sangre (the blood)
le lait la leche (the milk)
la minute el minuto (the minute)
le nez la nariz (the nose)
l'auto el auto (the car)
la couleur el color (the colour)
le sel la sal (the salt)
le doute la duda (the doubt)
le fruit la fruta (the fruit)
le nuage la nube (the cloud)
In the case of auto, the French word for car, the definite article le is replaced with l' because the noun starts with a vowel sound. However, the indefinite article une is feminine in the phrase une auto. Compare this with the masculine indefinite article un in un lac which means "a lake."
Many French and Spanish nouns share the same gender. This is evidence that the two languages are related. Despite the similarity of the two languages, though, certain nouns do not share the same gender.