noun
Japanese big-ear radix; pond snail
A freshwater snail species, Radix auricularia japonica. Used in biological and ecological contexts.
この池にはモノアラガイがたくさん生息している。
Many pond snails live in this pond.
The name likely derives from 物洗い (ものあらい, 'washing things') + 貝 (がい, 'shellfish'), but the exact origin is uncertain.