What is to open wide; to gape, as if to allow the entrance or exit of anything. 't is now the very witching time of night, When churchyards yawn. Shak called?

yawn — To open wide; to gape, as if to allow the entrance or exit of anything. 't is now the very witching time of night, When churchyards yawn. Shak. (Webster's 1913.)

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