Scottish or dialectal adjective meaning stupid, dull-witted, or foolish.
From 'dult' (a foolish person) + '-ie' (Scottish diminutive/adjective suffix). The '-ie' ending is characteristic of Scots English.
The '-ie' suffix in Scottish English (like 'bonnie' or 'doilie') often softens a word or makes it affectionate—so 'dultie' is almost a cute way to call someone silly!
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