[steyn] 
,| 1. | a discoloration produced by foreign matter having penetrated into or chemically reacted with a material; a spot not easily removed. |
| 2. | a natural spot or patch of color different from that of the basic color, as on the body of an animal. |
| 3. | a cause of reproach; stigma; blemish: a stain on one's reputation. |
| 4. | coloration produced by a dye that penetrates a substance, as wood. |
| 5. | a dye made into a solution for coloring woods, textiles, etc. |
| 6. | a reagent or dye used in treating a specimen for microscopic examination. |
| 7. | to discolor with spots or streaks of foreign matter. |
| 8. | to bring reproach or dishonor upon; blemish. |
| 9. | to sully with guilt or infamy; corrupt. |
| 10. | to color or dye (wood, cloth, etc.) by any of various processes that change or react with the substance chemically. |
| 11. | to color with something that penetrates the substance. |
| 12. | to treat (a microscopic specimen) with some reagent or dye in order to color the whole or parts and so give distinctness, contrast of tissues, etc. |
| 13. | to produce a stain. |
| 14. | to become stained; take a stain: This fabric stains easily. |
stain (stān)
n.
A reagent or dye that is used for staining microscopic specimens.
A procedure in which a dye or a combination of dyes and reagents is used to color the constituents of cells and tissues.
