inessential

Used of a work of art, a production that adds nothing of interest to the creator's portfolio. Does not necessarily imply that the work is bad per se, though mediocrity at best is often assumed. Often only of interest to fanboys and completists.

U2's most inessential work has got to be Pop.

by Lady Csyde December 3, 2005

nessential

Not only necessary, but also essential.

Air is nessential to life.

by MAGICXX1 December 24, 2009