[frawst, frost] 
| 1. | a degree or state of coldness sufficient to cause the freezing of water. |
| 2. | Also called hoarfrost. a covering of minute ice needles, formed from the atmosphere at night upon the ground and exposed objects when they have cooled by radiation below the dew point, and when the dew point is below the freezing point. |
| 3. | the act or process of freezing. |
| 4. | coldness of manner or temperament: We noticed a definite frost in his greeting. |
| 5. | Informal. a coolness between persons. |
| 6. | Informal. something that meets with lack of enthusiasm, as a theatrical performance or party; failure; flop. |
| 7. | a milk shake, frappe, or similar drink: a chocolate frost. |
| 8. | to cover with frost. |
| 9. | to give a frostlike surface to (glass, metal, etc.). |
| 10. | to ice (a cake, cookies, etc.). |
| 11. | to bleach selected strands of (a person's hair) in order to create highlights. |
| 12. | to kill or injure by frost: a freezing rain that badly frosted the tomato plants. |
| 13. | to make angry: I was frosted by his critical comment. |
| 14. | to become covered with frost or freeze (often fol. by up or over): The windshield has frosted over. |
| 15. | (of varnish, paint, etc.) to dry with a film resembling frost. |
| 16. | degree of frost, British. the degree of temperature Fahrenheit below the freezing point: 10 degrees of frost is equivalent to 22°F. |
| hoar·frost (hôr'frôst', -frŏst', hōr'-) n. Frozen dew that forms a white coating on a surface. Also called white frost. |
frost
|
frost (frôst)
n.
A deposit of minute ice crystals formed when water vapor condenses at a temperature below freezing.
| frost (frôst) Pronunciation Key
A deposit of tiny, white ice crystals on a surface. Frost forms through sublimation, when water vapor in the air condenses at a temperature below freezing. It gets its white color from tiny air bubbles trapped in the ice crystals. See more at dew point. |
| hoarfrost (hôr'frôst') Pronunciation Key
Frozen dew that forms a white coating on a surface. |
hoarfrost
deposit of ice crystals on objects exposed to the free air, such as grass blades, tree branches, or leaves. It is formed by direct condensation of water vapour to ice at temperatures below freezing and occurs when air is brought to its frost point by cooling. Hoarfrost is formed by a process analogous to that by which dew is formed on similar objects, except that, in the case of dew, the saturation point of the air mass is above freezing. The occurrence of temperatures below 0 C (32 F) is not enough to guarantee the formation of hoarfrost. Additionally, the air must be initially damp enough so that when cooled it reaches saturation, and any additional cooling will cause condensation to occur. In the absence of sufficient moisture, hoarfrost does not form, but the water in the tissues of plants may freeze, producing the condition known as black frost.
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