Plural or emphatic form of 'amid,' meaning surrounded by or in the middle of multiple things.
From Old English 'on middan' (in the middle), shortened to 'amid' by Middle English; 'amids' represents a rarely-used variant or archaic plural form reflecting dialectal English from the 16th-17th centuries.
You'll almost never see 'amids' in modern English because we stopped pluralizing prepositions centuries ago, but seeing it in old texts is like finding a fossil of how people's grammar actually changed over time.
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