When used with paper, it generally means making a bunch of holes in a line, such that the paper will tear easily along that line.

When tearing an object, there is a certain amount of energy required to start the tear and a certain amount of energy per unit length required to continue it. In most cases, the energy required to start the tear makes up the greatest part of the total energy required to tear something in half. Think about tearing a piece of paper: the hardest part is right at the beginning; once it starts to tear, it comes apart easily. This leads to the somewhat counterintuitive fact that tearing an object along a perforated line requires more effort, not less. The perforations actually only assist in keeping the tear straight.

Per"fo*rate (?), v. t. [imp. & p. p. Perforated (?); p. pr. & vb. n. Perforating.] [L. perforatus, p.p. of perforare to perforate; per through + forare to bore. See Bore, v.]

To bore through; to pierce through with a pointed instrument; to make a hole or holes through by boring or piercing; to pierce or penetrate the surface of.

Bacon.

© Webster 1913.

Per"fo*rate (?), Per"fo*ra`ted (?), a.

Pierced with a hole or holes, or with pores; having transparent dots resembling holes.

© Webster 1913.