essential Definition

1. Absolutely necessary.

Thesaurus: necessary, vital, crucial, needed, required, requisite, indispensable.
2. Relating to the basic or inner nature of something or its essence.

Thesaurus: innate, inherent, basic, core, central, fundamental, cardinal.

1. Something necessary.
2. A basic or fundamental element, principle or piece of information.

Form: the essentials (often)