v. & n.
v. 1 intr. (often foll. by down) descend rapidly like a bird of prey. 2 intr. (often foll. by on) make a sudden attack from a distance. 3 tr. (often foll. by up) colloq. snatch the whole of at one swoop.
n. a swooping or snatching movement or action. at (or in) one fell swoop see FELL(4).
[ perh. dial. var. of obs. swope f. OE swapan: see SWEEP ]