sapping
nounThe art of excavating trenches of approach under the musketry-fire of the besieged.
nounThe undermining of a river’s bank, especially if it is a cliff, by the moving water and its suspended grit.
verbPresent participle of
The art of excavating trenches of approach under the musketry-fire of the besieged.
nounThe undermining of a river’s bank, especially if it is a cliff, by the moving water and its suspended grit.
verbPresent participle of