A scalpel, lance or lancet.

A utility knife, boxcutter, or Exacto knife.

(dated) A curved knife used by shoemakers.

The distance from the bottom of a thing to its surface; depth. / The third dimension apart from width and height; the z-axis. / The further place relevant to one's current position. / The essence, core, the heart of a matter. / (of the heart, the soul) The most sensitive spot. / An unknown, dark period of time.

straight, direct

(transitive) To send, to dispatch. / (transitive, figuratively) To compel to move, to push, to propel.

(transitive) To turn away someone who asked for a favor with a made-up excuse; to get rid of, to send away.

Without anyone hearing or seeing, quietly, silently.

(of a person) Quiet, not talking much, reserved.

The act of sending, consignment, dispatch. / The act of compelling to move, propulsion, impulse.