電鈕

电钮
diànniǔ
push button (electric switch)

CEDICT

button (on an electrical appliance or electronic device)

Wiktionary

在電器開關或調節等設備中用手操作的部分，多以塑膠等絕緣材料製成。

重編國語辭典

Entry Composition

1 電 diàn
  1. lightning
  2. electricity
  3. electric (bound form)
  4. to get (or give) an electric shock
  5. phone call or telegram etc
  6. to send via telephone or telegram etc
2 鈕 niǔ button