Am

1. v Present tense, first person, singular form of the verb be. I am.

2. am is short for ante meridium, Latin for "before noon". This is used to define hours of the day: The meeting starts at 9 am. The opposite of am is pm?.

3. prep In German language, am is a contraction for the preposition? and [definite article]? "an dem", and as such occurs in some place names (similar to English upon?): Frankfurt am Main.

4. In chemistry, in the periodic table, Am is the chemical symbol for Americium.

5. In electrical engineering, AM is short for amplitude modulation.

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Trying hard to start with the most general meaning, going towards the more special. :-)

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