1. [n]  (in boxing) the act of one boxer holding onto the other to avoid being hit and to rest momentarily
2. [n]  a tight embrace
3. [n]  a small slip noose made with seizing
4. [v]  flatten the ends (of nails and rivets)
5. [v]  secure by clinching
6. [v]  hold in a tight grasp; "The boxer clinched his opponent"; "clench a steering wheel"

Clinch
A collection of verse by the highly regarded American poet and editor of Mag City.

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1. \Clinch\ (kl[i^]nch; 224), v. t. [imp. & p. p.
   {Clinched}; p. pr. & vb. n. {Clinching}.] [OE. clenchen,
   prop. causative of clink to cause to clink, to strike; cf. D.
   klinken to tinkle, rivet. See {Clink}.]
   1. To hold firmly; to hold fast by grasping or embracing
      tightly. ``Clinch the pointed spear.'' --Dryden.
   2. To set closely together; to close tightly; as, to clinch
      the teeth or the first. --Swift.
   3. To bend or turn over the point of (something that has been
      driven through an object), so that it will hold fast; as,
      to clinch a nail.
   4. To make conclusive; to confirm; to establish; as, to
      clinch an argument. --South.
   

2. \Clinch\, v. i.
   To hold fast; to grasp something firmly; to seize or grasp
   one another.
   

3. \Clinch\ (kl[i^]nch), n.
   1. The act or process of holding fast; that which serves to
      hold fast; a grip; a grasp; a clamp; a holdfast; as, to
      get a good clinch of an antagonist, or of a weapon; to
      secure anything by a clinch.
   2. A pun. --Pope.
   3. (Naut.) A hitch or bend by which a rope is made fast to
      the ring of an anchor, or the breeching of a ship's gun to
      the ringbolts.