"You are late.
Yet we had agreed on a schedule! ”
A time slot?
Are you sure?
The mistake is so common that it goes unnoticed.
The wrong use of gender for certain French words is heard more and more.
The French language is playful: in some cases, the masculine and the feminine are authorized, in others not.
The resulting confusion unfortunately leads to misuse of the language.
We then feel ashamed, illiterate, as though dispossessed of our language.
These rules, we thought we had mastered them.
It seemed obvious to us that they were part of us, since that blessed school age when we embraced the tortuous rules of grammar and spelling.
Do not panic!
The Académie Française is of great help to this, and gives a very simple explanation: timetable is a masculine word, so the custom is to say a timetable.
It would be attested in the French language since the 19th century.
Horaire is a "borrowing from Italian orario, in the same sense", and is also used in the masculine.
The immortals of the Academy point out that its frequent feminization is justified by the fact that it is preceded by the elided article the, which creates confusion on the gender of the word.
Its common use in the plural is also a factor of error, because "the mark of the plural overrides that of the genres."
Just as with the word "afternoon", the rule of which is that it must be preceded by a masculine article, the established gender of the hourly term cannot be replaced by the feminine.
The wise have spoken!