to be missing, to be absent, to have left (remaining)
Janice y yo nos lo pasábamos tan bien que empezó a faltar al trabajo.
Janice and I were having such a good time that she started missing work.
— Uno de los nuestros (1990)
Y a mi hija no le va a faltar absolutamente nada.
And my daughter will want for absolutely nothing.
— Relatos salvajes (2014)
Señora, cómo cree que voy a faltar.
Ma'am, how could you think I would miss it?
— Y tu mamá también (2001)
No tienes que faltar al colegio.
You don't have to miss school.