noun
ivory shell; cockle
Refers to bivalve mollusks of the family Veneridae, commonly known as Venus clams or hard clams. In Japanese contexts, it often specifically denotes the species Meretrix lusoria (Japanese hard clam).
潮干狩りで灰貝をたくさん採った。
We gathered a lot of ivory shells during clam digging.
灰貝は味噌汁の具にすると美味しい。
Ivory shells are delicious when used in miso soup.
蛤 (hamaguri) is the common Japanese clam (Meretrix lusoria), often used in clear soups and sushi. 灰貝 (haigai) is a broader term that can refer to various Venus clams, including 蛤, but is less common in everyday language.
浅蜊 (asari) is the Japanese littleneck clam (Ruditapes philippinarum), smaller and more commonly used in miso soup and pasta. 灰貝 refers to larger, harder-shelled clams.
The kanji 灰 (hai, 'ash') and 貝 (kai, 'shellfish') likely refer to the ashy color of the shell. The alternate spelling 伏貝 uses 伏 (fusu, 'to lie face down'), possibly describing the clam's habit of lying buried in sand. The exact origin is uncertain.