crumb

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A very small piece broken from a baked item, such as a cookie, cake, or bread.
2. n. A small fragment, scrap, or portion: eraser crumbs; not a crumb of kindness for you.
3. n. The soft inner portion of bread.
4. n. Slang A contemptible, untrustworthy, or loathsome person.
5. v. To break into very small pieces; crumble.
6. v. To cover or prepare with very small pieces of bread.
7. v. To brush (a table or cloth) clear of small scraps or fragments of food.
8. v. To break apart in very small pieces: a solid cake that won't crumb.

Century Dictionary and Cyclopedia

1. n. A morsel: specifically, a minute piece of bread or other friable food broken off, as in crumbling it; hence, a very small fragment or portion of anything.
2. n. The soft inner part of a loaf of bread or cake, as distinguished from the crust.
3. To break into small pieces with the fingers: as, to crumb bread into milk.
4. . To crumble bread into; prepare or thicken with crumbs of bread.
5. In cookery, to cover or dress with breadcrumbs, as meat, etc.; bread.
6. Same as crump.

Wiktionary

1. n. A small piece which breaks off from baked food (such as cake, biscuit or bread).
2. n. figuratively A bit, small amount.
3. n. The soft internal portion of bread, surrounded by crust.
4. n. A mixture of sugar, cocoa and milk, used to make industrial chocolate.
5. n. slang A nobody, worthless person.
6. n. slang A body louse.
7. v. To cover with crumbs.
8. v. To break into crumbs or small pieces with the fingers; to crumble.

GNU Webster's 1913

1. n. A small fragment or piece; especially, a small piece of bread or other food, broken or cut off.
2. n. Fig.: A little; a bit.
3. n. The soft part of bread.
4. v. To break into crumbs or small pieces with the fingers.

WordNet 3.0

1. v. break into crumbs
2. v. remove crumbs from
3. n. small piece of e.g. bread or cake
4. n. a very small quantity of something
5. v. coat with bread crumbs
6. n. a person who is deemed to be despicable or contemptible