v. north. and Sc. [UN-2 3.] trans. To unfasten (a door).

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1819.  W. Tennant, Papistry Storm’d (1827), 46. Thus said, Don Andrew … Unslot his yett, and out gaed whiddin’.

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1855.  [Robinson], Whitby Gloss., s.v., To Unslot or Unsteck, to unlatch, to open.

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