ONlwSG

bacbòrd m. While Oftedal (1956, 71) derives SG bòrd ‘table’ from OEng. bord, 

SG bòrd and Ir. bord (< EG bord, bordd) go back to OEng. bord (< ON borð m.) rather than to ON borð itself (eDIL^˄; Oftedal 1956, 71), although ON borð is considered to have influenced the Gaelic word in some of its senses (Marstrander 1915a, 43, 121).

he derives (Lewis) bacbòrd /ˈbak ̩bɔːʀd/ ‘the windward side [of a vessel]’ (ibid., 103, 335) from ON bakborð nt. or bakborði m. ‘the port side of a vessel’, ‘originally the side the steersman turned his back to when the oar was fixed to the starboard (right-hand) side’ (Torp 1919, 14, s.v. ¹bak). However, given that one would normally expect post-stress ON -k to yield [ɡ̊] /ɡ/ in Scottish Gaelic rather than [ʰk] /k/, 

Oftedal 1956, 99–100; 1972, 120; Sommerfelt 1962, 75–76; Cox 1992, 139–40.

and given that ON ð does not normally yield a plosive in Gaelic, 

ON ð yields a plosive in Gaelic only in the following exceptional circumstances: the cluster ON rð yields EG rdd (rt) /rd/ in the case of Norddmann (Nortmann) ‘Northman’ (< ON norðmann acc. m.) on a few occasions: di Norddmannaibh AU 836, la Nortmanoibh FM i 406.5; also with loss of the dental in do Normandaiḃ Cog. 16.4; also in i crichaiḃ Scithia ⁊ Dacia ⁊ Gathia ⁊ Northmann LL 171 b49, but which has been expanded by Hogan in CRR 7 as Northmannia (all quoted in eDIL^˄, s.v. Nortmann), ‘en litterær form’ (Marstrander 1915a, 111). However, the development is seen as an adoption of English usage (Greene 1976, 76) – all other references in AU have Latin declension (e.g. Nord(d)mannis AU 869, 927, 934, Nord(d)mannorum AU 841, 869, 874, 880) (Cox 2007b, 72–73). In place-names on the west of Scotland, final ON -fǫrð acc. m. ‘fiord’ yields SG (lenited) -phort ‘landing-place; harbour’ via morphemic substitution (Cox ibid., 74–70), s.v. port.

it seems more likely that bacbòrd is a loan from Scots backburd ‘the larboard or left side of a boat’ (SND^˄), itself no doubt a borrowing from ON bakborð or bakborði – the broader sense of the Gaelic word presumably evolving in a context in which the position of the oar was not so fixed.

The form of this word given in dictionaries (e.g. MacApline 1832, HSS 1828, Dwelly 1911, MacLennan 1925) is bac-bhòrd with lenition of the final element, and this is derived by MacLennan, Stewart (2004, 408), McDonald (2009, 339) and Ó Muirithe (2010) from ON bakborði, but this is unlikely for the same reasons as above and because there is no reason for the lenition of ON b to SG bh. However, the Scots loan-word bacbòrd may have been adapted as though it were an original Gaelic closed compound of bac + bòrd 

Via folk etymology, with bac ‘thole or oar-cleat; rowlock; the space between the tholes’ (< EG bacc (eDIL^˄), s.v. bac) and bòrd in the sense ‘plank, strake, side of vessel’ as in deasbhòrd (Thomson 1996a, s.v. starboard), bòrd-beulaibh (Dwelly 1911: ‘starboard side of a ship’), bòrd clì (Thomson ibid., s.v. port) and bòrd-cùlaibh (Dwelly ibid.: ‘port side of a ship’).

with primary stress on the adjectival element and lenition of the (final) nominal element.

Thurneysen 1975, 146; Calder 1972, 131–33. Contrast the failure of lenition in the nominal element in Ir. acarsuidhe, a ‘gaelicisation’ of Ir. acarsóid, s.v. acaire.