Scottish National Dictionary (1700–)
HARDHORN, adv. Tightly, firmly. Cf. Hard, III. and Horn, I. 1. (3).
Sc. 1761 Haliburton & Hepburn Magopico 36–7:
His principle exercises are to bolt upright, every now and then, with his eyes shut hardhorn, then lean down again upon the pulpit, and seem to fall into a slumber, with an arm extended on each side of the book.
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"Hardhorn adv.". Dictionary of the Scots Language. 2004. Scottish Language Dictionaries Ltd. Accessed 17 Dec 2017 <http://www.dsl.ac.uk/entry/snd/hardhorn>
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