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ad¹

(ăd)

An advertisement.

ad²

(ăd)

An advantage in tennis.

ad-

pref.

1. or ac- or af- or ag- or al- or ap- or as- or at- Toward; to. Before c, f, g, k, l, p, q, s, and t, ad- is usually assimilated to ac-, af-, ag-, ac-, al-, ap-, ac-, as-, and at-, respectively.

2. Near; at: adrenal.

[Latin, from ad, to; see ad- in the Appendix of Indo-European roots.]

abbr.

1. active duty

2. air-dried

3. or AD anno Domini

4. A/D analog/digital

5. athletic director

-ad

suff.

In the direction of; toward: cephalad.

[From Latin ad, to; see ad- in the Appendix of Indo-European roots.]

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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