Stack \Stack\, v. t. [imp. & p. p. Stacked; p. pr. & vb. n. Stacking.]

[Cf. Sw. stacka, Dan. stakke. See Stack, n.]

To lay in a conical or other pile; to make into a large pile; as, to stack hay, cornstalks, or grain; to stack or place wood.

To stack arms (Mil.), to set up a number of muskets or rifles together, with the bayonets crossing one another, and forming a sort of conical pile.

Source: Webster's Revised Unabridged Dictionary (1913)