Probably a miscorrection of inset, itself a misreading of muset (see musetn.1).The quot. is from the second quarto of the play; the first quarto of 1611 reads ‘insets’.
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meuse1523
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musser1611
1611 L. BarryRam-Alleyii. i. sig. C 2 We can finde, Your wildest paths, your turnings and returnes, Your traces, squats, the mussers, formes and holes, You yongmen vse.
This entry has been updated (OED Third Edition, March 2003; most recently modified version published online December 2019).