godan verb (-ru), transitive verb
to cover with; to smear; to sprinkle
Obsolete verb meaning to cover or smear something with a substance, or to sprinkle something over a surface. Replaced in modern Japanese by 塗る (ぬる) for smearing/coating and まぶす for sprinkling/coating with powder.
See also: 塗す
In old documents, the expression 'to sprinkle salt' can be found.
昔は傷に薬草をまぶって治療した。
Long ago, they treated wounds by smearing medicinal herbs on them.