We don't have synonyms for hallan yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are hallah, allan and harlan.
(n) :
(dialectal, Ireland, Scotland, Northumbria, Cumbria, Lancashire) The passage or space between the outer and inner door of a cottage; the partition between the passage and the room.
(n) :
(dialectal, Ireland, Scotland, Northumbria, Cumbria, Lancashire) The passage or space between the outer and inner door of a cottage; the partition between the passage and the room.