And every tongue, through utter drought
Was withered at the root;
We could not speak, no more than if
We had been choked with soot.

from Samuel Taylor Coleridge – Rime Of The Ancient Mariner on Rap Genius

Meaning

A startling and vivid description of the sailor’s thirst; tongues do not have roots, but Coleridge uses the word to suggest their tongues were completely dry, from base to surface.
‘Withered’ complements this as it conjures the image of a limp, pitiful plant on its last legs.

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