Definition - A figure of speech where conjunctions that are usually omitted are kept and used in close succession.
Note: The rhetorical purpose is to slow the prose's rhythm and endow it with, say, solemnity or dignity.

Example -
He likes to use polysyndeton and asyndeton and prolepsis and paralipsis whenever he can — but he hates tmesis to pieces.

Etymology -
The word derives from the Greek poly, many + syndeton, bound together with.

Oxford English Dictionary -
Its first citation is from 1589:
"Ye haue another maner of construction which they called Polisindeton [sic] we may call him the couple clause for that euery clause is knit and coupled together with a coniunctiue."
(Puttenham Eng. Poesie iii. xvi. (Arb.) 186)

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