An archaic or poetic form meaning all-powerful; a variant or shortened form of 'almighty.'
From Old English 'eallmihtig' (all-mighty), combining 'eall' (all) and 'mihtig' (mighty, powerful). 'Almight' appears in Middle English texts as a variant before 'almighty' became the standard form.
Reading Old English and Middle English texts, you find a fascinating variety of spellings for what we now call 'almighty'—showing that even our most sacred religious vocabulary was spelled flexibly until printing standardized English orthography in the 16th century.
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