A Sow

1. A female pig.
2. A female bear, she-bear.
3. A channel that conducts molten metal to molds.
4. A mass of metal solidified in a mold.
5. (derogatory, slang) A contemptible, often fat woman.
6. A sowbug.
7. (military) A kind of covered shed, formerly used by besiegers in filling up and passing the ditch of a besieged place, sapping and mining the wall, etc.

The plural form swine is now obsolete in this sense.

(mass of metal solidified in a mold): ingot

(contemptible woman): bitch, cow