Necessary.
Necessary for survival but not synthesized by the organism, thus needing to be ingested.
Being in the basic form; showing its essence.
Really existing; existent.
Very important; of high importance.
Having the nature of essence; not physical.
Such that each complementary region is irreducible, the boundary of each complementary region is incompressible by disks and monogons in the complementary region, and no leaf is a sphere or a torus bounding a solid torus in the manifold.
Idiopathic.
A necessary ingredient.
A fundamental ingredient.
Unearned gain.
Sauce used for pasta.
A dark savoury sauce prepared from stock and usually meat juices; brown gravy.
Extra benefit.
Curry sauce.
A pale sauce prepared from a roux with meat fat; a type of béchamel sauce.
To make gravy.