Yes, there are nouns in French that do not end in "s" to indicate the plural form. 1. Some words that already end in -s or end in -z do not add an s to form the plural E.g., le cas, les cas and le gaz, les gaz 2. Some (not all) words that end in -ail or -au add an x instead of an s: E.g., travail -> travaux; général -> généraux 3. Some words that end in -ou add an x: E.g., bijou -> bijoux 4. Many (but not all) words that end in -eu, -eau, and -au generally take an x: E.g., lieu -> lieux, eau -> eaux, etc 5. Words that form irregular plural forms: E.g., ail -> aulx (in older usage, but more commonly written as ails today), ciel -> cieux, oeil -> yeux On the other hand, I can't think of a French word that is the same in the singular and plural forms other than words that already end in -s or -z.

All words that ends with -s, -x or z. Le souris (the mouse), les souris (the mice). Le fils (the boy), les fils (the boys) Le gaz (the gas), les gaz (the gases) La voix (the voice), les voix (the voices) Also, there are words which end with an -x in plural, like taureau/taureaux (bull), cheval/chevaux (horse), beau/beaux (beautiful)...

of cours they are words that not ends ''s'' like words ends 'al' hopital = les hopitaux , journal = les journaux etc but chcal dont ends ''aux'' like others '' les chacals '' and ther is words how have not plural.

There are some words that are singular but mean a group of things, like "la vaisselle" (the dishes). I know there are a handful of those but I can oly think of that one right now. Oh, maybe dough, that's "la pâte", you can't really make it plural because "les pâtes" is another thing (pasta).

Thanks!