v1.0
Published 01/10/24
abhsadh m. [ˈaus̪əɣ], gen. abhsaidh [ˈaus̪i], ‘slackening sail, tug at a sheet (rope); easing, ceasing, restricting; heeding’ is frequently 
MacBain 1896; Henderson 1910, 127–28, 138; McDonald 1972; McDonald 2009, 361; Ó Muirithe 2013, 13.
derived from ON hálsa vb ‘to clew up or slacken sail’, recte ON halsa with a short stressed vowel (Marstrander 1915a, 61, 114; de Vries 1962). ON halsa yields EG allsaḋ (Meyer 1906, 81; Bugge 1912, 292; Marstrander ibid.; eDIL˄), with loss of initial h- and the addition of a final Gaelic fricative ḋ after the verbal noun morpheme ‑aḋ of weak a-verbs in Early Gaelic (Thurneysen 1975, 446–47); hence SG allsa, allsadh, 
MacBain 1896; Dwelly 1911; MacLennan 1925; represented by Marstrander’s transcription (?Argyllshire) allsa [ɑʟsə] (ibid.).
which develops into abhsadh with vocalisation in Gaelic of the lateral (Cox 2002b, 15–16 and fn 14) in more northerly/westerly dialects, cf. the Lewis village name Gabhsann derived from ON *Galt-sund ‘(the) hog-crossing’ (Cox 2022, 718–22).
Falk (1912, 69 – noted by Vendryes 1913, 231) compares Ice. *halsan f. (leg. hálsan; Cleasby 1874: ‘a clewing up the sail’) with Ir. allsadh; Mohr (1939, 170: halsan) suggests Ice. hálsan is a borrowing from Old Norse or Low German.
Derivatives: allsaich vb ‘to suspend, reprieve; jerk; lean to one side’ (HSS 1828; Dwelly 1911).