Etymology

Always derived from the ON neut. pl. n. represented by OIcel lǫg ‘law; law community, law-district’ (earlier *lagu), a semantically specialized pl. usage of lag (neut.) ‘stratum, layer; laying in order; companionship, fellowship; market price, tax; thrust, stab; regular time; air, tune; degree’, which was borrowed into late OE as lagu (usually fem. sg., rarely neut. pl.; see SPS). ON lag is explained as a formation on the a-grade (*lag-) of the commonplace str. v. PGmc *legjan- (as in OE licgan, OIcel liggja etc.). PGmc *lag- is less frequently attested in nominal usage in WGmc, thought it does feature in compounds (some with ON equivalents). However, it is only in the Scandinavian languages that derivations on this root are used in the sense ‘law’ (on the semantic development, see von See 1964: 175–81), and the earliest attestations of late OE lagu  (esp. its earliest bona fide record in IV Edgar (962–3), where it refers specifically to Danish law) belong to a Norse cultural context.

PGmc Ancestor

*lag-

Proposed ON Etymon (OIcel representative)

lǫg (pl.) ‘law; law community, law-district’
(ONP lag (sb.))

Other Scandinavian Reflexes

Far lóg, Icel lög, Norw log, Dan lov, Sw lag

OE Cognate

cp. orlæg ‘fate’, gelagu  ‘extent, surface (of sea)’, oferlagu ‘cloak’, ealdorlegu, feorhlegu ‘course of one’s life, death’

Phonological and morphological markers

Summary category

C3d

Attestation

On the distribution of late OE lagu (and its derivatives) see esp. Hofmann 1955: 150–4, 164, 185–6, 191–2, Godden 1980: 214–17, 221, Peters 1981b: 178–9, Fischer 1989, Pons-Sanz 2007: 61, 68–124, 231–5 and SPS 307–14., and for its occurrences in the 12c. Dance 2013.  Common and very widespread throughout ME.  

Occurrences in the Gersum Corpus

Gaw 790, 1643; Pe 285; Cl 188, 263, 723; Pat 259, 405; Erk 34, 200, 203 etc.; WA 757*, 1546, 1568 etc.

On the sense ‘style, manner’ in Gaw, see Clough (193), who suggests influence from OFr loi, AN lei.

Bibliography

MED laue (n.) , OED law (n.1) , HTOED , HTOED , HTOED , Dance lawe, Bj. 249, SPS 84–6, 307–14, de Vries lǫg, Mag. lög, Orel *laʒan, AEW læg; lagu (3)