noun
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.
(poker) A deceptive play whereby a player with a strong hand bets weakly or passively.
verb
(transitive, intransitive) To construct a barrier of sandbags (around).
(transitive) To strike someone with a sandbag or other object to disable or render unconscious.
(figurative, intransitive, originally US) To conceal or misrepresent one's true position, potential, or intent in order to gain an advantage; (originally poker) to pretend to have a weak hand, as a strategy.
(figurative, transitive) To blindside; to deceive; to undermine.
(restaurant kitchen jargon, intransitive, transitive) To premake dishes (prepare them in advance) (intransitive); to premake (dishes) (transitive).
To pretend to drink alcohol early on so that, as the night draws on, one can drink everybody else "under the table".