mochi offered when drawing the first water of the year
A traditional New Year practice: mochi is offered when drawing 若水 (wakamizu), the first water drawn on New Year's Day. This term is culturally specific and may not be widely known outside of traditional contexts.
See also: 若水
There is a custom of offering 'mizu no mochi' when drawing the first water of the year on New Year's Day.
Compound of 水 (mizu, 'water') and 餅 (mochi, 'rice cake'). The term is associated with the New Year's ritual of drawing the first water (若水).