noun
The muscular digestive organ found in birds, reptiles, and some other animals, used for grinding food.
鳥の砂嚢は、食べたものをすりつぶす役割がある。
A bird's gizzard serves to grind up the food it eats.
noun
A bag filled with sand, used for flood control, weight, or other purposes. Cross-referenced with 砂袋.
See also: 砂袋
洪水に備えて、家の前に砂嚢を積んだ。
We stacked sandbags in front of the house in preparation for the flood.
砂袋 is a more common word for 'sandbag' in everyday contexts; 砂嚢 is a technical or alternative term.
Compound of 砂 (sand) and 嚢 (sac, pouch). The 'gizzard' sense comes from the organ's sandpaper-like function; the 'sandbag' sense is a literal sand-filled bag.