Source : Webster's Revised Unabridged Dictionary (1913)

Hook \Hook\, n. [OE. hok, AS. h[=o]c; cf. D. haak, G. hake,
   haken, OHG. h[=a]ko, h[=a]go, h[=a]ggo, Icel. haki, Sw. hake,
   Dan. hage. Cf. {Arquebuse}, {Hagbut}, {Hake}, {Hatch} a half
   door, {Heckle}.]
   1. A piece of metal, or other hard material, formed or bent
      into a curve or at an angle, for catching, holding, or
      sustaining anything; as, a hook for catching fish; a hook
      for fastening a gate; a boat hook, etc.

   2. That part of a hinge which is fixed to a post, and on
      which a door or gate hangs and turns.

   3. An implement for cutting grass or grain; a sickle; an
      instrument for cutting or lopping; a billhook.

            Like slashing Bentley with his desperate hook.
                                                  --Pope.

   4. (Steam Engin.) See {Eccentric}, and {V-hook}.

   5. A snare; a trap. [R.] --Shak.

   6. A field sown two years in succession. [Prov. Eng.]

   7. pl. The projecting points of the thigh bones of cattle; --
      called also {hook bones}.

   {By hook or by crook}, one way or other; by any means, direct
      or indirect. --Milton. ``In hope her to attain by hook or
      crook.'' --Spenser.

   {Off the hooks}, unhinged; disturbed; disordered. [Colloq.]
      ``In the evening, by water, to the Duke of Albemarle, whom
      I found mightly off the hooks that the ships are not gone
      out of the river.'' --Pepys.

Crook \Crook\ (kr[oo^]k), n. [OE. crok; akin to Icel. kr[onac]kr
   hook, bend, SW. krok, Dan. krog, OD. krooke; or cf. Gael.
   crocan crook, hook, W. crwca crooked. Cf. {Crosier},
   {Crotchet}, {Crutch}, {Encroach}.]
   1. A bend, turn, or curve; curvature; flexure.

            Through lanes, and crooks, and darkness. --Phaer.

   2. Any implement having a bent or crooked end. Especially:
      (a) The staff used by a shepherd, the hook of which serves
          to hold a runaway sheep.
      (b) A bishop's staff of office. Cf. {Pastoral staff}.

                He left his crook, he left his flocks. --Prior.

   3. A pothook. ``As black as the crook.'' --Sir W. Scott.

   4. An artifice; trick; tricky device; subterfuge.

            For all yuor brags, hooks, and crooks. --Cranmer.

   5. (Mus.) A small tube, usually curved, applied to a trumpet,
      horn, etc., to change its pitch or key.

   6. A person given to fraudulent practices; an accomplice of
      thieves, forgers, etc. [Cant, U.S.]

   {By hook or by crook}, in some way or other; by fair means or
      foul.

Source : WordNet®

by hook or by crook
     adv : in any way necessary; "I'll pass this course by hook or by
           crook" [syn: {by any means}]