essential

essential [adj1] important, vital capital, cardinal, chief, constitutive, crucial, foremost, fundamental, imperative, indispensable, leading, main, necessary, necessitous, needed, needful, prerequisite, principal, required, requisite, righthand, wanted; concept 567 —Ant. accessory, auxiliary, inessential, minor, nonessential, secondary, subsidiary, unimportant essential [adj2] basic, fundamental absolute, basal, cardinal, cold, complete, congenital, connate, constitutional, deep-seated, elemental, elementary, ideal, inborn, inbred, inherent, innate, intrinsic, key, main, material, meat and potatoes*, name of the game*, nitty-gritty*, nub, perfect, primary, prime, primitive, principal, quintessential, substratal, underlying; concepts 546,549 —Ant. atypical, minor, secondary essential [n] necessity, basic ABCs*, bottom line*, brass tacks*, condition, element, essence, fire and ice*, fundamental, groceries*, guts*, heart, meat and potatoes*, must, name of the game*, nitty-gritty*, nuts and bolts*, part and parcel*, precondition, prerequisite, principle, quintessence, requirement, requisite, rudiment, sine qua non, stuff, substance, vital part, where one’s at*; concepts 646,661,826 —Ant. accessory, auxiliary, nonessential, subsidiary, throwaway, trivia