The present participle of 'balsam,' meaning to treat, anoint, or heal with balsam.
From 'balsam' used as a verb (to apply balsam) plus the present participle suffix '-ing.' This verbal form would appear in medical texts describing the treatment process.
The verb 'to balsam' almost never appears in modern English—its disappearance reflects how medical terminology shifts when treatments change. You don't hear about 'balsaming wounds' anymore because we have antibiotics.
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