The word releían is the imperfect form of releer in the third person plural.
See the full releer conjugation

releer

La llevaban consigo, la leían y releían, y no se quedaban satisfechos antes de saber grandes trozos de ella de memoria.
They carried it about with them, and read and reread, and could not be satisfied until they had committed large portions to memory.
Want to Learn Spanish?
Spanish learning for everyone. For free.
SpanishDict Premium
Have you tried it yet? Here's what's included:
Cheat sheets
No ads
Learn offline on iOS
Fun phrasebooks
Learn Spanish faster
Support SpanishDict