Listed by Shaw (1780: scor), Armstrong (1825: sgor), HSS (1828: sgòr) and Dwelly (1911: sgòr).
gen. sgòir [s̪kɔːɾʲ], and (with o ~ u alternation) sgùr [s̪kuːɾ],
Cited by Henderson (1910, 148).
also sgòrr [s̪kɔːɍ],
Listed by Armstrong (1825: scorr), HSS (1828: see sgòr), McAlpine (1832: sgorr [skôrr]), MacEachen (1842: sgòrr), Dwelly (1911: see sgòr) and MacLennan (1925).
gen. sgorra [ˈs̪kɔɍə], ~ sgùrr [s̪kuːɍ],
Listed by HSS (1828: see sgòrr), McAlpine (1832: sgurr [skûrr]), MacEachen (1842: sgùrr), Dwelly (1911: (sgòr)) and MacLennan (1925: see sgorr [sic]).
in the senses ‘sharp, steep hill rising by itself or a little, steep, precipitous height on another hill or mountain; peak, pinnacle; the tail of a bank in the sea, a concealed rock jutting into the sea’ (cf. Dwelly 1911, s.v. sgòr) is derived by Henderson (1910, 148: sgòr, sgùr ‘a sharp rock’) from ON skor ‘notch, incision; cleft, mountain ledge; canyon, gorge’ (NO; NSL˄). Henderson suggests that the long vowel in Gaelic may be due to the influence of Scots scaur (with a long vowel) ‘a sheer rock, crag, precipice, cliff, a steep hill from which the soil has been washed away etc.’ (< MScots scar < ON sker (SND˄); s.v. SG sgeir), but SG sgòr etc. most probably derives directly from Scots scaur.
So MacBain 1896; 1911.
On the other hand, Ir. scor m. (with its short vowel) in the sense ‘rock pinnacle’ may derive from a Northern English, short-vowel reflex scar. The reason for the short vowel in SG (Glengarry) sgor ‘a sharp corner or prominence’ (Dieckhoff 1932: [sgoR]) is unclear, but there may be conflation with SG sgor ‘notch’ (q.v.).
SG sgòrr (from sgòr) may be by analogy with SG tòrr ‘hill, heap’ (s.v. tiùrr); cf. also SG
pioradh besides piorradh, q.v., tiùr besides tiùrr, q.v., sgòradh besides sgòrradh, q.v.