Pabulum, n. [L., akin to pascere to pasture. See Pastor.]
The means of nutriment to animals or plants; food; nourishment; hence, that which feeds or sustains, as fuel for a fire; that upon which the mind or soul is nourished; as, intellectual pabulum.
Shades of meaning
Fernald has no entry of its own for pabulum; he lists it under food.
He lists it without comment; the entries above explain its neighbors.