scab

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A crust discharged from and covering a healing wound.
2. n. Scabies or mange in domestic animals or livestock, especially sheep.
3. n. Any of various plant diseases caused by fungi or bacteria and resulting in crustlike spots on fruit, leaves, or roots.
4. n. The spots caused by such a disease.
5. n. Slang A person regarded as contemptible.
6. n. A worker who refuses membership in a labor union.
7. n. An employee who works while others are on strike; a strikebreaker.
8. n. A person hired to replace a striking worker.
9. v. To become covered with scabs or a scab.
10. v. To work or take a job as a scab.

Century Dictionary and Cyclopedia

1. n. An incrusted substance, dry and rough, formed over a sore in healing.
2. n. The mange, or some mangy disease caused by the presence of a parasite, as an itch-insect; scabies.
3. n. A mean, paltry, or shabby fellow: a term of contempt.
4. n. Specifically, in recent use, a workman who is not or refuses to become a member of a labor-union, who refuses to join in a strike, or who takes the place of a striker: an opprobrious term used by the workmen or others who dislike his action.
5. n. In botany, a fungous disease affecting various fruits, especially apples and pears, in which a black mold appears, often distorting or destroying the fruit. It is usually followed by a brown scablike appearance, whence the name. The fungus producing the disease in apples and pears is Fusicladium dendriticum. The orange-leaf scab is produced by a species of Cladosporium. See Fusicladium.
6. n. In founding, any projection on a casting caused by a defect in the sand-mold.
7. Having to do with “scabs,” or made by them: used opprobriously: as, scab mills; scab labor; scab shoes.
8. To form a scab or scabby incrustation; become covered with a scab or scabs; specifically, to heal over; cicatrize; repair solution of continuity of a surface by the formation of a new skin or cicatrix.

Wiktionary

1. n. An incrustation over a sore, wound, vesicle, or pustule, formed during healing.
2. n. The scabies.
3. n. The mange, especially when it appears on sheep.
4. n. Several different diseases of potatoes producing pits and other damage on their surface, caused by Streptomyces -bacteria.
5. n. Short form for common scab, a relatively harmless variety of scab caused by Streptomyces scabies.
6. n. Any one of various more or less destructive fungus diseases attacking cultivated plants, and forming dark-colored crustlike spots.
7. n. A slight irregular protuberance which defaces the surface of a casting, caused by the breaking away of a part of the mold.
8. n. A mean, dirty, paltry fellow.
9. n. A worker who acts against trade union policies, especially a strikebreaker.
10. v. To get covered by a scab.
11. v. To act as strikebreaker.
12. v. To beg (for), cadge, bum

GNU Webster's 1913

1. n. An incrustation over a sore, wound, vesicle, or pustule, formed by the drying up of the discharge from the diseased part.
2. n. The itch in man; also, the scurvy.
3. n. The mange, esp. when it appears on sheep.
4. n. A disease of potatoes producing pits in their surface, caused by a minute fungus (Tiburcinia Scabies).
5. n. A slight irregular protuberance which defaces the surface of a casting, caused by the breaking away of a part of the mold.
6. n. A mean, dirty, paltry fellow.
7. n. A nickname for a workman who engages for lower wages than are fixed by the trades unions; also, for one who takes the place of a workman on a strike.
8. n. Any one of various more or less destructive fungus diseases attacking cultivated plants, and usually forming dark-colored crustlike spots.
9. v. To become covered with a scab.
10. v. to take the place of a striking worker.

WordNet 3.0

1. v. take the place of work of someone on strike
2. v. form a scab
3. n. someone who works (or provides workers) during a strike
4. n. the crustlike surface of a healing skin lesion