Sources

Trontyrrmoir, Trontyrrbeg c.1591 Pont map 2

“… contain the name Thrond, the appears in Trotternish, Skye, G Trondairnis, Throndar-nes.” Watson 2001 (1904), 68 [in discussion of ON element dalr]

N. here is euphonic, and is not heard in Gaelic Trau-dal. The word is Norse, “Trow” is the lower ground through which a river runs.” Gunn, 147

Trantle-mor, and beg Norse, trantr, snout, or projection of land, now pronounced “trantle” instead of “trauter,”: MacKay