What is "siege gun"

Siege \Siege\, n. [OE. sege, OF. siege, F. si[`e]ge a seat, a siege; cf. It. seggia, seggio, zedio, a seat, asseggio, assedio, a siege, F. assi['e]ger to besiege, It. & LL. assediare, L. obsidium a siege, besieging; all ultimately fr. L. sedere to sit. See Sit, and cf. See, n.]

1. A seat; especially, a royal seat; a throne. [Obs.] ``Upon the very siege of justice.''
   --Shak.

   A stately siege of sovereign majesty, And thereon sat a woman gorgeous gay.
   --Spenser.

   In our great hall there stood a vacant chair . . . And Merlin called it ``The siege perilous.''
   --Tennyson.

2. Hence, place or situation; seat. [Obs.]

   Ah! traitorous eyes, come out of your shameless siege forever.
   --Painter (Palace of Pleasure).

3. Rank; grade; station; estimation. [Obs.]

   I fetch my life and being From men of royal siege.
   --Shak.

4. Passage of excrements; stool; fecal matter. [Obs.]

   The siege of this mooncalf.
   --Shak.

5. The sitting of an army around or before a fortified place for the purpose of compelling the garrison to surrender; the surrounding or investing of a place by an army, and approaching it by passages and advanced works, which cover the besiegers from the enemy's fire. See the Note under Blockade.

6. Hence, a continued attempt to gain possession.

   Love stood the siege, and would not yield his breast.
   --Dryden.

7. The floor of a glass-furnace.

8. A workman's bench.
   --Knught.

   Siege gun, a heavy gun for siege operations.

   Siege train, artillery adapted for attacking fortified places.