v1.0
Published 01/10/24
fuidh int. ‘an exclamation of disgust etc.’ has a number of variant forms:
A. SG fuidh, fuith, fuigh [fuj]
(i) fuidh: Armstrong 1825: ‘“an exclamation of disgust”, fuidh ort “shame on you!”’; MacBain 1896 (and 1911), s.v. fich: ‘“nasty!”, also dial. fuich, fuidh ... Cha bhi fuidh ach far am bi fàile [lit. “there’s no odour without a smell”, which AFB˄ equates with Eng. there’s no smoke without fire]’; Dwelly 1911: ‘see fich’; note also that Dieckhoff (1932) gives [f(ui)j] under fuich (B).
(ii) fuith: HSS 1828, s.v. fuith: ‘uttered on perceiving a bad odour’, also s.v. [Eng.] fy: ‘fuith!’; MacLeod and Dewar 1839: idem; MacEachen 1842: ‘fie!, shame!’; Dwelly 1911: ‘see fich’; Dieckhoff 1932: ‘see fuich’;
(iii) fuigh: Mackay 1897, 96: ‘an exclamation used in feeling any unpleasant smell’; Calder 1972, 326: ‘fich, fuigh “fy!”’.
B. SG fuich [fuiç]
Armstrong 1825: ‘an exclamation of disgust’; McAlpine 1832: ‘fuich fuich [fŭĕch] [fŭĕch] “fie fie!, pshaw!”’; MacBain 1896 (and 1911), s.v. fich: ‘“nasty!”, also dial. fuich, fuidh’; Dwelly 1911: ‘see fich’; MacLennan 1925, s.v. fich: ‘fuich “fy!, a bad smell, a strong expression of disgust”’; Dieckhoff 1932: ‘fuich fuich [f(ui)j f(ui)j] [sic, see under (A)] “an interjection of disgust”’; Ó Murchú 1989, 347: ‘/fux´/ “an interjection disclaiming need for thanks, an expression of mild dissent”’; Wentworth 2003: ‘[fuiç] “pooh!”; AFB˄: ‘/fiç/ [sic] “eew! yuck!; booh! hiss!”: Cha bhi fuidh [sic] ach far am bi fàile “no smoke without fire”’ (see under A (i)).
C. fich [fiç]
MacBain 1896 (and 1911): ‘“nasty!”, also dial. fuich, fuidh’; Dwelly 1911: ‘“nasty!”, fich ort “an expression of disgust or contempt”’; MacLennan 1925: ‘fich, fuich “fy!, a bad smell, a strong expression of disgust”’; Dieckhoff 1932: ‘see fuich’; Calder 1972, 326: ‘fich, fuigh “fy!”’; note also that AFB˄ gives /fiç/ under fuich (A).
SG fuidh, fuith and fuigh are homophonous. Fuidh etc. and fuich are first attested in Armstrong 1825, while SG fich only appears towards the end of the 19th century.
MacBain (1896; 1911) equates fich with Eng. fie, ON fý and Germ. pfui, noting also ‘dialectal fuich, fuidh, which leans on [Old] Norse fúi [m.] “rottenness”’, while MacLennan (1925) equates fich and fuich with ON fúi. Mackay (1897, 96) derives fuigh from Ice. fui [leg. fúi] ‘rottenness’; Stewart (2004, 410: ‘a response to a stench, expression of disgust’) derives fich and fuich and McDonald (2009, 355: ‘fy!’) fich, fuich, fuidh and fuigh all from ON fúi.
ON fúi, or oblique fúa, would formally yield SG *futhaidh *[ˈfu-i], or *futha *[ˈfu-ə]. On the other hand, the Old Norse interjection *fý (NO: fy) ‘fie’ 
MacBain (1896; 1911) writes fý, ?after Cleasby’s (1874) OIce. fý ‘fye’; cf. Norw. fy ‘ugh! whew! (what a smell!); fie!, shame! (reproach)’ (Haugen 1984). Both Old Norse and Icelandic go back to Lat. f ī, as does Eng. fie (OED˄).
might be expected to yield SG *f ì *[fiː], cf. the Old Norse river name *Grýta < SG *Grìoda (Oftedal 1954, 399–401 fn; 1956, 67).
SG fuidh (fuith, fuigh) is perhaps an adaptation of Eng. fie ‘an exclamation expressing, in early use, disgust or indignant reproach’ (OED˄). SG fich is likely to be a loan from Scots feech [fɪç] ‘an exclamation of disgust at a foul smell, pain as on touching something hot, impatience or disappointment’. While SG fuich might be an earlier adaptation of Scots feech 
Cf. Munro 1843, 82: SG ‘[ f ]uidh, or fuith, an interjection of disgust; in Scotch, fich!’
(also found as foich), it may simply be an adaptation of Scots wheech [ʍiç] ‘an exclamation of disgust on smelling a stench’ (SND˄), cf. CSc. *Hvarf with initial [ʍ]-, which developed into SG [f]-, hence Blaeu 1654 Faro Head NC259747 (Eng. Cape Wrath), later yielding [pʰ]- via back-formation, hence c.1630 Parro Head and modern SG Am Parbh (Cox 2022, 505–06).
Although the back vowel in SG fuich may also show a degree of influence from native SG och, oich. EG uch, och, ach ‘an exclamation generally denoting woe, ah! alas!’ (eDIL˄) yields SG och [ɔx], [ox] ‘an exclamation used to express pain, grief, impatience, disagreement etc.’. SG och has the variant ochan, containing the nominally diminutive, here agentive, suffix -an -[an], and both have variant forms with palatalised finals, viz oich [ɔiç], [oiç] and ochain [ˈɔxaɲ], [ˈoxaɲ], perhaps (at least partly) in imitation of vocative masculine singular nouns, any radical broad final consonants of which are palatalised in Scottish Gaelic. The form oichean occurs also. SG ochòn (also ochòin) is taken to consist of och + òn, from OG ón ‘this, that’, an indeclinable neuter demonstrative pronoun (MacBain 1896 and 1911: ochòin; MacLennan 1925: och-ón; Watson 1932, 371: och òn); more likely SG ochòn is an archaism (with primary stress attracted to the long vowel), and the equivalent of EG uchán, uchón ‘alas’, derivatives of uch, och, ach, above (Vendryes 1996). Contrast the spelling given in AFB˄: o chóin /ɔ xoːNʲ/.
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Scots feuch [fjuːx] ‘an exclamation of disgust at a foul smell, pain, impatience or disappointment’ (SND˄, s.v. 3feuch) would seem to be an unlikely source for any of the Gaelic forms here, as this would be expected to yield SG *fiùch *[fjuːx].