Alexander Dyce, A General Glossary to Shakespeare's Works

inn — “Thou most beauteous,” RICHARD II., v. 1. 13 ; “shall I not take mine ease in mine inn?” 1 HENRY IV., iii. 3. 79. In the first of these passages inn, according to Steevens, means “a dignified habitation;” according to Mason, “a house of entertainment, and is opposed to alehouse in the following line [the next line but one];” and according to Mr. Staunton merely“abode.” On the second passage Percy observes, “To ‘take mine ease in mine inne’ was an ancient proverb, not very different in its application from that maxim, ‘Every man's house is his castle;’ for inne originally signified a house or habitation [Sax. inne, domus, domicilium]. When the word inne began to change its meaning, and to be used to signify a house of entertainment, the proverb, still continuing in force, was applied in the latter sense, as it is here used by Shakespeare.”