I. sand‧bag¹ /ˈsændbæɡ/ noun [countable]
a bag filled with sand, used for protection against floods, explosions etc

[TahlilGaran] Dictionary of Contemporary English ▲

II. sandbag² verb (past tense and past participle sandbagged, present participle sandbagging)

1. [intransitive and transitive] to put sandbags around a building in order to protect it from a flood or explosion

2. [transitive] to treat someone unfairly in order to prevent them from doing something or being successful

[TahlilGaran] Dictionary of Contemporary English ▲