de fondo

underlying; long-distance

→ de
phrase Rare #28,540
underlying; long-distance Used for something deep or substantive, and also in sports for long-distance or cross-country events.
SP: Hay un problema de fondo que todavía no hemos resuelto.
EN: There is an underlying problem that we still haven't solved.

Tom a menudo va esquiando de fondo.

Tom often goes cross-country skiing.

Me han dicho que eres una corredora de fondo muy buena.

I've been told you're a very good long-distance runner.

Hizo todo el trabajo de fondo.

He did all the background work.

Hay algo más de fondo.

There's something more to it.

— Bullet Train (2022)

Esta mujer no lleva ningún debate de fondo.

This woman isn't engaging in any substantive debate.

— R.A.F. Facción del ejército rojo (2008)