Deeper Dive: am

am [AS. am, eom, akin to Gothic im, Icel. em, Olr. am, Lith. esmi, L. sum., Gr. Zend ahmi, Skr. asmi, fr. a root as to be. See Are, and cf. Be, Was.]

The first person singular of the verb be, in the indicative mode, present tense. See Be.
God said unto Moses, I am that am. Exod. iii. 14.

-- Webster's unabridged 1913

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