from The Century Dictionary.
- To cease from encumbering.
Sorry, no etymologies found.
A peck of oats was a favourite offering at her shrine in St. Paul's by those who wished for favours; and according to Sir Thomas More she owed her popular name because wives unhappy in their union so offered in the hope that she would _uncumber_ (_i. e._, disencumber) them of their husbands.
Wylgeforte call her St. Uncumber, bycause they reken that for a pecke of otys she will not fayle to uncumber theym of theyr housbondys_. "