消しゴム
けしゴム · keshigomu · JLPT N4 · noun
eraser
🧽 消し (erase, from 消す) + ゴム (gum = rubber): an erase-rubber
消し is the stem of 消す, to erase or turn off. ゴム is a loanword from Dutch gom, meaning rubber, which is why it is written in katakana. Together they mirror the British English word for eraser: a rubber.
消 — water 氵 + 肖 (phonetic)
消 is a semantic-phonetic compound: the water radical 氵 indicates the meaning, while 肖 (xiào) supplies the sound. It originally described water dwindling or melting away, and from there extended to the modern senses of vanishing, dissolving, and dispelling.