'sparks'(Modern English )
This rare n. is usually related to flake (OED n.2, MED n.1; see further flakes (n.)), and Sw (snö)flanka 'snow' provides a direct comparandum, strengthening the case for an ON etymon. As McGee notes (391), the distribution of the MnE dial word does not preclude the possibility of ON loan.
Proposed ON Etymon (OIcel representative)
Other Scandinavian Reflexes
Phonological and morphological markers
Only otherwise attested in MED in a1425 PPl.C (Lond-U V.88); MnE dial flank is attested by EDD from the S/SW.
Occurrences in the Gersum Corpus