nécessaire

Nécessaire is a French adjective meaning necessary, required, essential, or obligatory. It describes something that must be done, present, or used. The form is the same for masculine and feminine in the singular (un outil nécessaire, une raison nécessaire); the plural is nécessaire for both genders (les outils nécessaires, les raisons nécessaires). In everyday language, it is common to use synonyms such as essentiel, indispensable, or obligatoire.

As a noun, le nécessaire refers to the essential items or basic needs—the things one must have. For example, on peut dire “Tout le nécessaire pour partir en voyage” meaning all the basics one needs to travel. The plural les nécessaires is less common than using les nécessités, which is another noun form conveying the idea of necessities.

Etymology and related forms: nécessaire comes from Latin necessarius, from necessitas meaning necessity. It entered Old French as necessaire and evolved into the modern adjective and noun. It is cognate with English necessary, Spanish necesario, Italian necessario, and other Romance-language equivalents.

Usage and grammar: in formal and standard French, il est nécessaire de + infinitive expresses a general necessity, while il est nécessaire que + subjonctif conveys a requirement about another subject. The phrase il faut que is a more idiomatic alternative in many contexts. When describing something as necessary for a purpose, one can use être nécessaire à + noun or à + infinitive (e.g., un outil nécessaire à la réparation). The word’s gender and number align with the noun it modifies; feminine singular is the same spelling as masculine singular, and both plural forms are nécessaires.