Etymology

Formal derivation from ON is just possible, but the sense in context (‘I schal gruch þe no grwe for grem þat fallez’) almost certainly confirms  identification with an OFr derived term (which is the modern consensus): (1)  ME gru 'a bit, a whit' < OFr gru 'grain, meal', a loan of a Gmc *grūt (cp. OE grūt ‘coarse meal, peeled grain, groats; draff, dregs, the spent malt after brewing; finely ground flour’, EFris grūt ‘sediment’, MLG, MDu grūt(e) ‘a kind of ferment’, MHG grūz ‘grain (of sand or wheat)’, Norw dial grūt ‘sediment’). The analogous OE phrase nan grot 'not a whit' (see DOE s.v. grot) was perh. the direct model for the ME idiom. (2) The earliest commentators struggled with the phrase and Emerson (1922: 405) proposed derivation from a Scandinavian gru 'horror, dread, fear'. This would be the only instance of such a n. in ME and the nearest form at this period is the related v. ME gruen 'to be terrified, shudder, tremble; of mirth, manner, behaviour: to be disturbed, be troubled', which is most likely simply cognate with a number of related continental Scandinavian verbs, probably derived themselves from LG (< PGmc *grūw-; see further gryed and Dance.). Moreover the sense 'horror' does not fit well into the context of Gaw 2251.

PGmc Ancestor

(1) *grūt; (2) *grūw-

Proposed ON Etymon (OIcel representative)

(ONP )

Other Scandinavian Reflexes

Dan gru; cp. Norw gruva, ODan gruve, grye, Dan grue, OSw grūva sik, Sw gruva sig

OE Cognate

(1) cp. grūt ‘coarse meal, peeled grain, groats; draff, dregs, the spent malt after brewing; finely ground flour’

Phonological and morphological markers

Summary category

DD2

Attestation

(1) MED has a handful of other citations, all in the phrase no ~, not a ~ (etc.) ‘not a bit’: two are from N/NWM alliterative verse (WA and Erk), but the others are from further afield (a1450(1412) Hoccl. RP (Hrl 4866); a1500(1456) Whan lordschype (Dub 516); see further OED, EDD s.v. gru sb.). (2) A n. grue ‘shivering’ (etc.) is not recorded in English before 1820.  The related v. ME grūen is cited by MED a handful of times from Cursor onwards; mainly N/EM, but also a1450 PPl.B (Bod 814) (and a1450 Pride Life (ChrC-Dub), though MED suspects this is an error for greven). Mainly Scots, Irish, N/EM in PDE dial. usage (EDD).

Occurrences in the Gersum Corpus

Gaw 2251

Bibliography

MED grū(e (n.1) , OED grue (n.1) , HTOED , Dance grwe; (1) AND gros (2), DEAF gru (m.), FEW Germanismes *grūt; (2) OED grue (n.4) , OED grue (v.1) , MED grūen (v.) , EDD grue (v.1, sb.1 and adj.1), Torp NnEO gruv (1), Falk-Torp grue (vb.), Hellquist gruva sig, Tamm gruva sig, Nielsen grue (II), Lloyd and Lühr grūēn, Kluge-Seebold grauen, de Vries/Toll gruwen