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Am¹

The symbol for americium.

Am²

abbr.
Bible

Amos

Am.

abbr.

1. America

2. American

abbr.

1. airmail

2. amplitude modulation

3. or AM Latin anno mundi (in the year of the world)

4. or AM or am ante meridiem

5. Latin artium magister (Master of Arts)

Usage Note: By convention, 12 AM denotes midnight and 12 PM denotes noon. Because of the potential for confusion, it is advisable to use 12 noon and 12 midnight.

(ăm)

First person singular present indicative of be.

[Middle English, from Old English eom; see es- 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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