Andrew Marr’s TV series Great Scots had James Boswell as its first subject (watch here on BBC iPlayer for another couple of weeks, or here on YouTube).
Scotland and England had united in 1707, and Marr noted that London in the early and mid-18th century was full of ambitious Scots. James Boswell was one of them. Following the Act of Union the English accent was considered the most prestigious regional variant, and many ambitious Scots felt obliged to abandon their Scottish accent and dialect words (such as wee, bairn and youthy), if they wanted to get on in the world. Johnson’s influential dictionary of 1755 contained few Scottish words or Scottish senses of words, even though five of his amanuenses were Scots. Some examples (copied verbatim) are:
bursar: Students sent as exhibitioners to the universities in Scotland by each presbytery, from whom they have a small yearly allowance for four years.
holograph: This word is used in the Scottish law to denote a deed written altogether by the granter’s own hand.
minute: the first draft of any agreement in writing; this is common in the Scottish law.
drotchel: An idle wench; a sluggard. In Scottish it is still used.
scranch: to grind somewhat crackling between the teeth. The Scots retain it.
sponk: a word in Edinburgh which denotes a match, or anything dipt in sulphur that takes fire.
Wee is in Johnson’s dictionary. He describes it as having a Saxon root and gives the definition ‘In Scotland it denotes small or little’. Youthy is in the Dictionary, but without reference to Scotland; Johnson defines it as ‘Young, youthful’ but then goes on to add ‘A bad word’. Bairn is not in.
James Boswell wrote the first-ever dictionary of the Scots language, although he did not complete or publish it. It was discovered only recently in the Bodleian Library in Oxford (I wrote a post on it, here, a few years ago).