Right down the dam gross-bellied frogs were cocked
On sods; their loose necks pulsed like sails. Some hopped:

from Seamus Heaney – Death of A Naturalist on Rap Genius

Meaning

The deep (“bass”) sound is coming from frogs sitting on the peat sods. “Gross” puns on “large” and “rude” or “disgusting.” The frogs' necks inflate as they croak, revolting the young observer.

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