✅ Necessary is the best word to describe something vital for the fulfillment of a need (A working engine is necessary for the car to run).
✅ Essential describes something that is particularly necessary, without which there would be dire consequences (It’s essential to bring water on a camping trip).
✅ Necessary and essential can be used interchangeably, though essential has a stronger meaning.
✅ Both words can also be exaggerated or humorous ways to describe things that aren’t technically life or death, but are important in some way (My morning coffee is essential to my health and the health of those around me).
Try describing something that is necessary to you with the help of Grammar Coach.