- not essential; not necessary: Nonessential use of gasoline was forbidden during the war.
- a nonessential thing or person.
- not essential; not necessary
- biochem (of an amino acid in a particular organism) able to be synthesized from other substances
- a nonessential person or thing
adj.also nonessential, 1717, from non- + essential (adj.). Attested as a noun from 1806. adj.
- Being a substance required for normal functioning but not needed in the diet because the body can synthesize it.