not essential; of relatively no importance; unnecessary
Biochem. designating biological compounds, esp. amino acids, required by living systems, that can be made in adequate amounts from other dietary constituents
noun
a nonessential person or thing
See nonessential in American Heritage Dictionary 4
(nŏnˌĭ-sĕnˈshəl)
adjective
Having little or no importance; not essential.
Biochemistry Being a substance that is required for normal functioning but does not need to be included in the diet because of the body's ability to synthesize it from other nutrients.