ショウ, さいわ.い, きざ.し, よ.い, つまび.らか, あき, さか, さち, ひろ, まさ, やす, ゆき, よし, あきら, さき, さむ, ただ, なか, なが

auspicious, happiness, blessedness, good omen, good fortune

JLPT1 G7 S10 F1273

As per # (abundant) + altar/the supernatural → propitious *omen* of abundance to come → *happiness*.

[Full Kanji Etymology List]