scab

noun

1. the incrustation that forms over a sore or wound during healing.
2. Veterinary Pathology. a mangy disease in animals, especially sheep; scabies.Compare itch(def 10).
3. Plant Pathology.
   1. a disease of plants characterized by crustlike lesions on the affected parts and caused by a fungus or bacterium.
   2. one of these crustlike lesions.
4. a worker who refuses to join a labor union or to participate in a union strike, who takes a striking worker’s place on the job, or the like.
5. Slang. a rascal or scoundrel.
6. Metallurgy.
   1. a projection or roughness on an ingot or casting from a defective mold.
   2. a surface defect on an iron or steel piece resulting from the rolling in of scale.
7. Carpentry. a short, flat piece of wood used for various purposes, as binding two timbers butted together or strengthening a timber at a weak spot.

verb (used without object), scabbed, scab·bing.

8. to become covered with a scab.
9. to act or work as a scab.

noun

1. the dried crusty surface of a healing skin wound or sore
2. a contagious disease of sheep, a form of mange, caused by a mite (Psoroptes communis)
3. a fungal disease of plants characterized by crusty spots on the fruits, leaves, etc
4. derogatory
   1. Also called: blacklega person who refuses to support a trade union’s actions, esp one who replaces a worker who is on strike
   2. (as modifier)scab labour
5. a despicable person

verb scabs, scabbing or scabbed (intr)

6. to become covered with a scab
7. (of a road surface) to become loose so that potholes develop
8. to replace a striking worker

n.mid-13c., “skin disease,” developed from Old English sceabb “scab, itch” (related to scafan “to shave, scrape, scratch”) and from Old Norse skabb “scab, itch,” both from Proto-Germanic *skab- “scratch, shave,” from PIE *(s)kep- “to cut, scrape, hack” (see scabies). Sense reinforced by cognate Latin scabies “scab, itch, mange” (from scabere “to scratch”). Meaning “crust which forms over a wound or sore” is first attested c.1400. Meaning “strikebreaker” first recorded 1806, from earlier sense of “person who refuses to join a trade union” (1777), probably from meaning “despicable person” (1580s), possibly borrowed in this sense from Middle Dutch. n.

1. A crust formed from and covering a healing wound.
2. Scabies or mange in domestic animals or livestock, especially sheep.

v.

1. To become covered with scabs or a scab.

1. A crust that forms over a healing wound, consisting of dried blood, plasma, and other secretions.

Informally, a worker who stays on the job while others go on strike. Also, a worker brought in to keep a plant operating when its work force is on strike. (See strikebreaker.)