c. 1300, "boundary marker," from Anglo-Latin bunda, from Old French bonde "limit, boundary, boundary stone" (12c., Modern French borne), variant of bodne, from Medieval Latin bodina, which is perhaps from Gaulish.
From mid-14c. as "an external limit, that which limits or circumscribes;" figuratively, of feelings, etc., from late 14c. From late 14c. as "limits of an estate or territory." Now chiefly in out of bounds, which originally referred to limits imposed on students at schools; the other senses generally have gone with boundary.