Thon
That, over there. A third demonstrative beyond 'this' and 'that', marking something further away or more pointedly identified. 'Thon man' is more specific than 'that man'; 'thon house' is the house we are both looking at, distant from us both.
Etymology
A conflation of Scots 'yon' and 'that'. The merger gave the language a third demonstrative at a useful remove: 'this' (here), 'that' (there, middle distance), and 'thon' (further again, or more emphatically identified). DSL traces literary attestations from at least 1818, with the form well-settled by the time S.E. Ferrier and Stevenson reached for it. James Fenton's _Hamely Tongue_ records the same construction live in Co. Antrim speech today, alongside compounds like 'thontim' (that occasion) and 'thonway' (in that manner).
In a sentence
Hoose! ca' ye thon a hoose? Thon's gude Glenfern Castle. - S.E. Ferrier, 1818
Ca' thon a leddy? - R.L. Stevenson, 1893
Thon wuz a sicht! - James Fenton, The Hamely Tongue (Co. Antrim)
Historical notes
Thon fills a gap that standard English has not quite filled. 'Yonder' tries, but is now archaic or self-consciously poetic; English speakers without thon end up using 'that one over there' or pointing. Ulster Scots and Scots speakers have it as part of the basic deictic system and use it without thinking. Stevenson borrowed the construction in Catriona to give Scottish dialogue its full shape.
Sources
- Dictionaries of the Scots Language (DSL), entry THON pron., adj. · dictionary
- Fenton, James. The Hamely Tongue: A Personal Record of Ulster-Scots in County Antrim. Ullans Press. · dictionary