islay

Origin

Derived from Scottish Gaelic Ìle, but probably ultimately of non-Indo-European (substrate) origin, along with other uncertain names in Scotland such as Skye, Lewis, and Arran. Watson (1926) hinted that a Proto-Brythonic/Proto-Celtic root connected to Gaulish *ilio (“flank, buttock”) or Welsh ilio (“to ferment”) might be behind the name. The silent s in this word, as in island, is due to an unetymological association with isle.