index card
US /ˈɪn.deks ˌkɑːrd/
UK /ˈɪn.deks ˌkɑːrd/

1.
ficha, tarjeta de índice
a small card used for writing notes, often for organizing information or for studying
:
•
She wrote her presentation notes on index cards.
Ella escribió sus notas de presentación en fichas.
•
He used index cards to study for his history exam.
Él usó fichas para estudiar para su examen de historia.