floor tiles
甎 centers on fired clay used as flat building material: floor tiles. The meaning is narrow and concrete, referring to a specific ceramic product.
甎 combines 專 (which may contribute sound) with 瓦 (tile, earthenware), suggesting a ceramic tile. The exact historical development is uncertain, but the phono-semantic structure is plausible.
The left side 專 looks like a specialized tool, and the right side 瓦 means tile. Imagine a craftsman using a special tool to shape clay into floor tiles.
For セン, picture a craftsman laying floor tiles and counting each one as a cent: cent -> セン, and every tile is worth a cent.