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The symbol for astatine.

abbr.

attotesla

(ăt; ət when unstressed)

prep.

a. In or near the area occupied by; in or near the location of: at the market; at our destination.

b. In or near the position of: always at my side; at the center of the page.

2. To or toward the direction or location of, especially for a specific purpose: Questions came at us from all sides.

3. Present during; attending: at the dance.

4. Within the interval or span of: at the dinner hour; at a glance.

5. In the state or condition of: at peace with one's conscience.

6. In the activity or field of: skilled at playing chess; good at math.

7. To or using the rate, extent, or amount of; to the point of: at 30 cents a pound; at high speed; at 20 paces; at 350°F.

8. On, near, or by the time or age of: at three o'clock; at 72 years of age.

9. On account of; because of: rejoice at a victory.

10. By way of; through: exited at the rear gate.

11. In accord with; following: at my request.

12. Dependent upon: at the mercy of the court.

13. Occupied with: at work.

Idiom:

at it Informal

Engaged in verbal or physical conflict; arguing or fighting: The neighbors are at it again.

[Middle English, from Old English æt; see ad- in the Appendix of Indo-European roots.]

at-

pref.

Variant of ad-.

abbr.

1. air temperature

2. ampere-turn

3. antitank

4. automatic transmission

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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