A necessary ingredient.
A fundamental ingredient.
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 meal which has been purchased and has been carefully packaged as to be taken and consumed elsewhere.
The preliminary part of a golfer′s swing when the club is brought back away from the ball.
A concession made by a labor union in the course of negotiations.
A restaurant that sells food to be eaten elsewhere.
An idea from a talk, presentation, etc., that the listener or reader should remember and consider.
(Of food) intended to be eaten off the premises from which it was bought.