der Taster
Translation
push-button, button, switch
Examples
Drücken Sie den roten Taster.
Press the red button.
Der Taster für das Licht ist kaputt.
The switch for the light is broken.
Grammar Patterns
der Taster (as subject/object) The button glows green.
Similar Words
Knopf (button), Schalter (switch)
Etymology
Derived from the verb 'tasten' (to feel, to touch). It refers to something you operate by touching.
Memory Tips
Think of it as something you 'tasten' (touch) to activate.