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ad·vec·tion

(ăd-vĕkshən)

1. The transfer of a property of the atmosphere, such as heat, cold, or humidity, by the horizontal movement of an air mass: Today's temperatures were higher due to the advection of warm air into the region.

2. The rate of change of an atmospheric property caused by the horizontal movement of air.

3. The horizontal movement of water, as in an ocean current.

[Latin advectiō, advectiōn-, act of conveying, from advectus, past participle of advehere, to carry to : ad-, ad- + vehere, to carry; see wegh- in the Appendix of Indo-European roots.]

ad·vective adj.

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advection

Advection of warm moist air over a cooler surface, such as water, causes fog.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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