he/she dropped it; it fell from his/her hands or possession
A mi hermana se le cayó el plato al piso.
My sister dropped her plate on the floor.
Se le cayó la salchicha al suelo.
The sausage fell to the ground.
Que es una pieza que se le cayó de su tambor.
That it's a piece that fell off his drum.
— P.K. (Peekay) (2014)
I think he dropped this.
He dropped his phone.
Se le cayó un botón a su abrigo.
A button fell off his coat.
He dropped the glass.
A él se le cayó su billetera, y ahora es mía.
He dropped his wallet, and now it’s mine.
Se le cayó el chorizo al suelo.
The sausage fell to the ground.