(A). Some food. “To have a peck,” is to have something
Hungry, or desirous of something to eat. Of course “peck” refers to
fowls, etc., which peck their food.
“When shall I feel peckish again.” —Disraeli: Sybil, book vi.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894