Acht
Property, ownership - usually with a jocular or contemptuous edge. 'Whas acht's thon?' = whose property is that? (= what's-his-name's that?). The construction often serves to identify someone obliquely or to disclaim ownership.
Etymology
From Scots 'aucht' (= property, possession), Older Scots. Cognate with Old English 'ǣht' (= possession) and Old Norse 'átt' (= property). The Norse-Old-English Germanic strand is the underlying root. Fenton documents the modern Antrim use in The Hamely Tongue. The construction 'whas acht?' has the dignified syntactic shape of an older possessive question, preserved here in spoken use.
In a sentence
"Whas acht's thon car parked across the lane?"
Historical notes
Acht is one of the words that survives in Co. Antrim Ulster Scots through Fenton's recording but is rare elsewhere. The phrase 'whas acht's thon?' is the diagnostic use - a way of identifying a person by who owns them or whose family they belong to, in the old rural sense of community knowledge. The slightly contemptuous edge is part of the social meaning: asking whose property someone is implies they are no-one's, or someone else's problem.
Sources
- Fenton, James. The Hamely Tongue: A Personal Record of Ulster-Scots in County Antrim. Ullans Press. · dictionary