adverb/a reˌɡaɲaˈdjentes/
reluctantly, grudgingly
“Los hermanos Amador, Raimundo y Rafael, arrastrados a un estudio a regañadientes (no se soportaban, y así siguen) por el productor Ricardo Pachón para dejar constancia en un disco de su arte.” — The Amador brothers, Raimundo and Rafael, reluctantly dragged into a studio (they couldn't stand each other, and still can't) by the producer Ricardo Pachón to record their art on a record.
Synonyms: a cara de perro, de mala gana
From regañar (“to gripe”).