Going back to the Dark Ages, there are many people and languages, that merged into what we now call Scotland – the Picts in the north, the Britons (Cumbric) around Strathclyde and the South of Scotland, the Anglo-Saxons of Lothian & the Borders, the Gaels coming over from Ireland to Dalriada (Argyll & Kintyre) bringing with them their language and Celtic Christianity and later on the Vikings (the northern & western Isles were for a few hundred years part of Norway & the Viking world) plus the influence of Norman French, Latin & even some Flemish through North Sea trading.
Where ever you travel throughout Scotland many of the very descriptive place names (naming places by its surrounding features in nature) and everyday phrases still reveal this rich heritage.
On our tours to the Highlands and the Hebrides, we will come across the beautiful Gaelic language (and for example pass the Sabhal Mor Ostaig Gaelic college http://www.smo.uhi.ac.uk/en/ , you can visit the National MOD Gaelic music & culture festival https://www.ancomunn.co.uk/ or start teaching yourself online some key Gaelic words.
In the lowlands and especially in Ayrshire on our visits to the Robert Burns (the most famous author in Scots) birthplace museum https://www.nts.org.uk/visit/places/robert-burns-birthplace-museum we will learn some Scots phrases.
On our tours of the Northern Isles, Shetland, Orkney as well in Caithness and throughout the North of Scotland we will touch on some Norn and Old Norse words.