Definify.com
Webster 1913 Edition
Sheathed
Sheathed
,Adj.
 1. 
Povided with, or inclosed in, sheath. 
2. 
(Bot.) 
Invested by a sheath, or cylindrical membranaceous tube, which is the base of the leaf, as the stalk or culm in grasses; vaginate. 
Webster 1828 Edition
Sheathed
SHE'ATHED
,pp.
             1. Put in a sheath; inclosed or covered in a case; covered; lined; invested with a membrane.
           2. a. In botany, vaginate; invested by a sheath or cylindrical membranaceous tube, which is the base of the leaf, as the stalk or culm in grasses.