SANDBAG

A sturdy sack filled with sand, generally used in large numbers to make defensive walls against flooding, bullets, or shrapnel.

A small bag filled with sand and used as a cudgel.

An engraver's leather cushion, etc.

To construct a barrier of sandbags around.

"We sandbagged the basement windows against the floodwaters."

To strike someone with a sandbag or other object to disable or render unconscious.

To conceal or misrepresent one's true position, potential, or intent in order to gain an advantage.