layered mochi; small mochi on top of a big mochi
A traditional New Year decoration or offering consisting of two round mochi stacked, often with a daidai on top.
During New Year's, we display layered mochi in the alcove.
two things heaped together; one on top of another
Figurative or descriptive use for any two items stacked; less common than the specific mochi sense.
The rice balls were packed in the lunch box like two things heaped together.
From 重ね (kasane, 'layering') + 餅 (mochi, 'rice cake'). The word literally describes the stacking of mochi.