UNDERCHARGE

Un′der‐charge″ (?), v. t. 1. 1. To charge below or under; to charge less than is usual or suitable for; as, to undercharge goods or services.
2. 2. To put too small a charge into; as, to undercharge a gun.
Undercharged mine (Mil.), a mine whose crater is not as wide at top as it is deep. W. P. Craighill.