Nourishment, n.
Etymology: [Cf. OF. norrissement.]
1. The act of nourishing, or the state of being nourished; nutrition.
2. That which serves to nourish; nutriment; food. Learn to seek the nourishment of their souls. Hooker.
Shades of meaning
Fernald has no entry of its own for nourishment; he lists it under food.
Where he writes about it:
Thus, we speak of food and drink, of wholesome, unwholesome, or indigestible food; but in a more scientific sense whatever, when taken into the digestive organs, serves to build up structure or supply waste may be termed food; the word is extended to plants to signify whatever taken in any way into the organism serves similar purposes; thus, we speak of liquid food, plant food, etc.; in this wider sense food is closely synonymous with nutriment, nourishment, and sustenance. — from food
Nourishment and sustenance apply to whatever can be introduced into the system as a means of sustaining life; we say of a convalescent, he is taking nourishment. — from food