'plunge'(Modern English )
Always derived from ON, cp. OIcel dumpa 'hit heavily, thump'. The wk. v. is rare in OIcel (with only a single citation in ONP), but a wider range of senses better paralleling the ME v. are evident in the modern Scandinavian reflexes, esp. Dan dumpe 'fall abruptly'. OED suggests that 'the sense of the word has evidently received onomatopoeic modification, from its suggestiveness of a dull abruptly-checked blow or thud, and of the action producing this'. Ult. connections are more speculative. There is evidence for a v. with full ablaut series on which ON *dumpa may have been formed, cp. e.g. Sw dial dimpa (see Hellquist s.v.), suggesting a Gmc *demp- from IE *dhemb(h)-. The root does not occur in OE, but various WGmc forms have been identified with it, e.g. Ger dumpen.
Proposed ON Etymon (OIcel representative)
dumpa 'hit heavily, thump'
(ONP dumpa (vb.))
Other Scandinavian Reflexes
Far dump, Icel dumpa, Norw dumpa, Dan dumpe
Phonological and morphological markers
N texts predominate in the ME citations of OED and MED.
Occurrences in the Gersum Corpus
Pat 362; WA 4487