The Collaborative International Dictionary of English v.0.48:

Sit \Sit\, v. i. [imp. Sat(Sate, archaic); p. p. Sat
   (Sitten, obs.); p. pr. & vb. n. Sitting.] [OE. sitten,
   AS. sittan; akin to OS. sittian, OFries. sitta, D. zitten, G.
   sitzen, OHG. sizzen, Icel. sitja, SW. sitta, Dan. sidde,
   Goth. sitan, Russ. sidiete, L. sedere, Gr. ???, Skr. sad.
   [root]154. Cf. Assess,Assize, Cathedral, Chair,
   Dissident, Excise, Insidious, Possess, Reside,
   Sanhedrim, Seance, Seat, n., Sedate, 4th Sell,
   Siege, Session, Set, v. t., Sizar, Size,
   Subsidy.]
   1. To rest upon the haunches, or the lower extremity of the
      trunk of the body; -- said of human beings, and sometimes
      of other animals; as, to sit on a sofa, on a chair, or on
      the ground.
      [1913 Webster]

            And he came and took the book put of the right hand
            of him that sate upon the seat.       --Bible (1551)
                                                  (Rev. v. 7.)
      [1913 Webster]

            I pray you, jest, sir, as you sit at dinner. --Shak.
      [1913 Webster]

   2. To perch; to rest with the feet drawn up, as birds do on a
      branch, pole, etc.
      [1913 Webster]

   3. To remain in a state of repose; to rest; to abide; to rest
      in any position or condition.
      [1913 Webster]

            And Moses said to . . . the children of Reuben,
            Shall your brothren go to war, and shall ye sit
            here?                                 --Num. xxxii.
                                                  6.
      [1913 Webster]

            Like a demigod here sit I in the sky. --Shak.
      [1913 Webster]

   4. To lie, rest, or bear; to press or weigh; -- with on; as,
      a weight or burden sits lightly upon him.
      [1913 Webster]

            The calamity sits heavy on us.        --Jer. Taylor.
      [1913 Webster]

   5. To be adjusted; to fit; as, a coat sits well or ill.
      [1913 Webster]

            This new and gorgeous garment, majesty,
            Sits not so easy on me as you think.  --Shak.
      [1913 Webster]

   6. To suit one well or ill, as an act; to become; to befit;
      -- used impersonally. [Obs.] --Chaucer.
      [1913 Webster]

   7. To cover and warm eggs for hatching, as a fowl; to brood;
      to incubate.
      [1913 Webster]

            As the partridge sitteth on eggs, and hatcheth them
            not.                                  --Jer. xvii.
                                                  11.
      [1913 Webster]

   8. To have position, as at the point blown from; to hold a
      relative position; to have direction.
      [1913 Webster]

            Like a good miller that knows how to grind, which
            way soever the wind sits.             --Selden.
      [1913 Webster]

            Sits the wind in that quarter?        --Sir W.
                                                  Scott.
      [1913 Webster]

   9. To occupy a place or seat as a member of an official body;
      as, to sit in Congress.
      [1913 Webster]

   10. To hold a session; to be in session for official
       business; -- said of legislative assemblies, courts,
       etc.; as, the court sits in January; the aldermen sit
       to-night.
       [1913 Webster]

   11. To take a position for the purpose of having some
       artistic representation of one's self made, as a picture
       or a bust; as, to sit to a painter.
       [1913 Webster]

   To sit at, to rest under; to be subject to. [Obs.] "A
      farmer can not husband his ground so well if he sit at a
      great rent". --Bacon.

   To sit at meat or To sit at table, to be at table for
      eating.

   To sit down.
       (a) To place one's self on a chair or other seat; as, to
           sit down when tired.
       (b) To begin a siege; as, the enemy sat down before the
           town.
       (c) To settle; to fix a permanent abode. --Spenser.
       (d) To rest; to cease as satisfied. "Here we can not sit
           down, but still proceed in our search." --Rogers.

   To sit for a fellowship, to offer one's self for
      examination with a view to obtaining a fellowship. [Eng.
      Univ.]

   To sit out.
       (a) To be without engagement or employment. [Obs.] --Bp.
           Sanderson.
       (b) To outstay.
       (c) To elect not to participate in, as a dance or a hand
           of cards.

   To sit under, to be under the instruction or ministrations
      of; as, to sit under a preacher; to sit under good
      preaching.

   To sit up, to rise from, or refrain from, a recumbent
      posture or from sleep; to sit with the body upright; as,
      to sit up late at night; also, to watch; as, to sit up
      with a sick person. "He that was dead sat up, and began to
      speak." --Luke vii. 15.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sitten \Sit"ten\, obs.
   p. p. of Sit, for sat.
   [1913 Webster]