ɪˈsenʃəl adj. & n. --adj. 1
absolutely necessary;
indispensable. 2
fundamental,
basic. 3 of or constituting
the essence of a
person or
thing. 4 (of a disease)
with no
known external stimulus or
cause; idiopathic. --n. (esp. in pl.) a basic or indispensable
element or thing. øessential element
any of
various elements required by
living organisms
for normal growth. essential
oil a
volatile oil derived
from a
plant etc. with
its characteristic odour. øøessentiality n. essentially adv. essentialness n. [ME f. LL essentialis (as ESSENCE)]