noun
CaribbeanIn the production of rum: the lees or dregs from the fermentation of a batch of cane juice or molasses, which contains active yeasts and is typically reserved and left to ferment in a vat or pit before being used to start the fermentation of fresh batches. In early use also: †refuse or dregs from the process of sugar production, used in the fermentation of rum (obsolete).
The use of dunder to start fermentation is characteristically associated with Jamaican rum.
Origin
Late 18th century; earliest use found in Edward Long (1734–1813), planter and commentator on Jamaican affairs. Apparently irregularly from Spanish redundar to overflow, with loss of the initial syllable and retention of the Spanish infinitive ending.
noun
Scottish, Irish1A loud, reverberating noise; a loud rumble.
2A resounding, heavy blow.
Origin
Late 18th century. From dunder.
verb
Scottish, Irish1To make a loud, deep resounding noise; to reverberate, rumble.
2To knock, bang, or fall on something with a loud, resounding noise, especially to knock loudly and repeatedly on a door. Followed by a prepositional phrase, especially with on or at.
Origin
Early 18th century; earliest use found in Battle of Harlaw. Probably from a form in a Scandinavian language from Middle Low German donnern, donren, dondern.