Etymology

Commentators generally agree on the meaning of this n. and derive it from a n. probably in some way related to the PGmc st. v. *flaxan- 'flay', which is attested in ON as flá and OE as flēan. The precise etymology is problematic, however, and the need to adduce ON input is debated: EVG compares Icel fláttr 'flaying' (which also occurs as a simplex and in compounds in ON, see ONP) and reconstructs ON *flaht-  while Holthausen (1923: 135) suggests instead a native OE *fleaht, and OED acknowledges both possibilities, and further connects English flake (n.2) and flaw (n.2) with similar senses. Goll compares (and Osgood simply cites) ON flag (OIcel flag 'sod of turf, place where the turf has been cut out' (cp. LG flag, flagg 'flat land')) without comment (see OED s.vv. flag n.2 and flag n.1 and EPNE s.v. *flage for more secure instances of this word in English).
 

PGmc Ancestor

*flax- or *flaʒ-

Proposed ON Etymon (OIcel representative)

flag 'sod of turf, place where the turf has been cut out'; fláttr 'flaying'
(ONP flaga (sb.); fláttr (sb.))

Other Scandinavian Reflexes

Icel fláttur, Norw flått; cp. Far flag, Icel flag, Norw dial flag, Sw dial flag, flaga; Norw dial flaga, Dan dial flave, Sw flaga

OE Cognate

?*fleaht

Phonological and morphological markers

Summary category

CC1c

Attestation

MED has a handful of citations of its n. flaught, all possibly from Yks. (the earliest is (c1396) Doc.York in Sur.Soc.35). N and Sc in MnE dial (see EDD, OED)

Occurrences in the Gersum Corpus

Pe 57

Bibliography

MED flaught (n.) , OED flaught (n.1) , HTOED , de Vries fláttr, Mag. fláttur, EPNE flaught (sb.1 and v.1), Seebold *flaha-; MED flag(ge (n. 2) , OED flag (n.2) , HTOED , EDD flag (sb.2 and v.), Bj. 158, 237-8, de Vries flag, Mag. flaga (4), Orel *flaʒan, EPNE *flage