Swap (?), v. t. [imp. & p. p.Swapped (?); p. pr. & vb. n.Swapping.] [OE. swappen to strike; cf. E. to strike a bargain; perh. akin to E. sweep. Cf. Swap a blow, Swap, v. i.] [Written also swop.] 1. To strike; — with off. “Swap off his head!” Chaucer.
2. To exchange (usually two things of the same kind); to swop. Miss Edgeworth.