The character REI is made up of two elements: shimesu and yutaka.
SHIMESU: the divine spirit come down to inhabit the altar
YUTAKA: the mountain and the wooden offering-vase containing food: two ears of rice, and the container over-flowing with food: – abundance.
These two elements combined give the idea of an altar abundantly provided with food-offerings, before which one waits for the descent of the divine…
… matsuri = CELEBRATION .
– – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – –
– – – Tamura Nobuyoshi Shihan, Aikido, étiquette et transmission p. 34