淄 is best known as the 淄河 (Zi River) in Shandong and in the city name 淄博. It also has a literary sense 'black' (a loan for 缁), seen in the saying 涅而不淄 - staying unstained even when dipped in dark dye.
Supplies the sound. The right element 甾 gives the exact zī reading. It is rare on its own (used in chemistry for the steroid nucleus) and carries no meaning into the river name 淄.
