Hŭb, n.

noun

n. [See Hob.] 1. The central part, usually cylindrical, of a wheel; the nave.

  1. The hilt of a weapon; as, to drive a dagger into a body up to the hub. Halliwell.
  2. A rough protuberance or projecting obstruction; as, a hub in the road. [U. S.]
  3. A goal or mark at which quoits, &c., are cast.
  4. A projection on a wheel for the insertion of a pin; as, a crank-pin hub. [Written also hob.]

Up to the hub, as far as possible in embarrassment or difficulty, or in business, like a wheel sunk in mire; to a great extent; deeply involved.