to sprinkle or scatter (over something), e.g. to sprinkle salt, pepper, or seasoning on food.
サラダに塩とオリーブオイルを振りかけた。
I sprinkled salt and olive oil on the salad.
ご飯にふりかけを振りかけて食べた。
I sprinkled furikake on rice and ate it.
夜空に星のように光を振りかけたようだった(比喩的表現)。
It was as if light had been sprinkled like stars across the night sky (figurative).