be-all and end-all

[ bee-awl uh nd end-awl ]
/ ˈbiˌɔl ənd ˈɛndˌɔl /

noun

the central and all-important part: His work was the be-all and end-all of his existence.

Origin of be-all and end-all

First recorded in 1595–1605

British Dictionary definitions for be-all and end-all

be-all and end-all

noun informal

the ultimate aim or justification to provide help for others is the be-all and end-all of this group
often jocular a person or thing considered to be beyond improvement