knacker

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Chiefly British A person who buys worn-out or old livestock and slaughters them to sell the meat or hides.
2. n. Chiefly British A person who buys discarded structures and dismantles them to sell the materials.

Century Dictionary and Cyclopedia

1. n. That which knacks or knocks; in the plural, two pieces of wood or bone used as a plaything by boys, who strike them together by moving the hand; castanets; bones.
2. n. A maker of knacks, toys, or small work.
3. n. A collar- and harness-maker, employed chiefly by farmers.
4. n. Acolliers' horse.
5. n. One whose occupation is the slaughtering of diseased or useless horses; also, one who deals in such horses, whether for use or slaughter.
6. n. A man who dismantles and sells the materials of old houses, ships, etc.

Wiktionary

1. n. One who makes knickknacks, toys, etc.
2. n. One of two or more pieces of bone or wood held loosely between the fingers, and struck together by moving the hand; a clapper.
3. n. A harness maker.
4. n. One who slaughters and (especially) renders worn-out livestock (especially horses) and sells their flesh, bones and hides.
5. n. One who dismantles old ships, houses etc., and sells their components.
6. n. Ireland, UK, offensive A member of the Travelling Community; a Gypsy.
7. n. Ireland, offensive, slang A person of lower social class; a chav, skanger or scobe.
8. v. To tire out, become exhausted.

GNU Webster's 1913

1. n. One who makes knickknacks, toys, etc.
2. n. One of two or more pieces of bone or wood held loosely between the fingers, and struck together by moving the hand; -- called also clapper.
3. n. Obs. or Prov. Eng. a harness maker.
4. n. engraving One who slaughters worn-out horses and sells their flesh for dog's meat.

WordNet 3.0

1. n. someone who buys up old horses for slaughter
2. n. someone who buys old buildings or ships and breaks them up to recover the materials in them