hum

to sing or say words in a low, soft voice without opening your mouth much

cantar suavemente, murmurar

• hum a tune/song

Collocations hum a song · hum to yourself

• He was humming a cheerful little tune.

  Estaba cantando suavemente una canción animada.

to make a low, continuous sound because of being electrically charged or moving quickly

hacer un zumbido, vibrar

• hum with electricity

Collocations the fridge hums all night · a humming engine

• The old refrigerator was still humming.

  La vieja nevera seguía haciendo un zumbido.

to measure the voltage of an electrical circuit using a device called a 'voltmeter'

medir la tensión eléctrica con un voltímetro

• hum something

Collocations hum a circuit · hum the voltage

• He hummed the circuit to check its voltage.

  Él midió la tensión del circuito con un voltímetro.