also: ゴマしお
noun
gomasio; roasted sesame seed and salt mixture
A condiment made from roasted sesame seeds ground with salt; often sprinkled on rice or onigiri.
おにぎりにごま塩をふりかける。
I sprinkle gomasio on the rice ball.
noun
salt-and-pepper hair; dark hair streaked with gray
Describes hair that is a mix of black and white, resembling the condiment. Often used in the phrase ごま塩頭.
父は最近ごま塩頭になってきた。
My father's hair has recently become salt-and-pepper.
ふりかけ is a broader category of dry condiments sprinkled on rice, while ごま塩 specifically refers to the sesame-salt mixture.
Compound of ごま (sesame) and 塩 (salt). The hair sense is a metaphorical extension based on the visual similarity.