‘swelling with round, smooth surface’(Modern English balgh)
Two possible sources have been suggested: (1) Most authorities derive from an OE (Angl.) adj. *balg (WS *bealg) with a basic sense ‘bulging’, i.e. an adj. formation on the pret. sg. stem of the str. vb. PGmc *belgan- (OE belgan ‘to swell with anger, become angry’; cp. bolne) (thus Emerson 1922: 402–3, TGD, OED, MED), cp. esp. PGmc *balg-i-z (OE (Angl.) belg (bælg, bylg etc.) ‘bag, pouch, sack; (pair of) bellows’ (and as a place-name element, see further VEPN), cp. Go balgs, OIcel belgr, OFris -balch, OHG, OS balg. (2) Alternatively, GDS (2712n) prefers to take the underlying meaning of the adj. as ‘smooth’, and on this basis suggests a comparison with ON bali 'a soft grassy bank, especially sloping down to the shore’ (CV), which has occasionally been suggested as the source ( so Harada 1961: 97, Kullnick 1902:14, Schmittbetz 1909: 13). However, OIcel bali is recorded only once by ONP (from a ms c. 1500) with a suggested meaning ‘?(elevated sand-)bank (at the shore)’), and (along with the Norw bale, with a similar sense) is best connected etymologically to the root of OIcel bǫllr, OHG bal ‘ball’, OE bealluc ‘testicle’ etc. and moreover it only gets us some of the way to the cluster -/lɣ/ in ME balʒ.
(1) *balg-; (2) *bal-
Proposed ON Etymon (OIcel representative)
bali 'a soft grassy bank, especially sloping down to the shore’
(ONP bali (sb.))
Other Scandinavian Reflexes
Icel bali, Norw bal
(1) cp. belgan (v.) ‘to swell with anger, become angry’ and belg (Angl.) (n.) (bælg, bylg etc.) ‘bag, pouch, sack; (pair of) bellows’; (2) cp. bealluc 'testicle'
Phonological and morphological markers
MED has a handful of occurrences in (N/EM) alliterative verse, plus the form balhew in the EAngl. (1440) PParv.(Hrl 221).
Occurrences in the Gersum Corpus
Gaw 967, 2032, 2172
TGD, followed by Barron, AW, PS and McGillivray, emend Gaw MS 967 bay to *balʒ (see TGDn, and also PS 966–7n); for defences of the MS reading, see Brett (1913: 162–3) and the notes in GDS and Vant.
MED balgh (adj. ), OED balgh (adj.) , HTOED , Dance balʒ; (1) Seebold belg-a-, Orel *ƀelʒanan; ƀalʒiz, Kroonen *belgan-; *balgi-, AEW belgan; bielġ, DOE belgan; gebelgan; belg, bylg, EPNE *balg, VEPN *balg; (2) de Vries bali, Mag. bali (1), Torp NnEO bale, Orel *ƀalluz, Kroonen *ballan-