From Wiktionary, the free dictionary
Borrowed from Latin quantitātem, accusative of quantitās, from quantus (“how much”).
quantidat f (usually uncountable)
- amount, quantity
c. 1250, Alfonso X, Lapidario, f. 2r:Et deſta manera puede tirar muchos fierros apegando ſe unos a otros faſta tamanna quantidat quãto pueda ſofrir.- And so it can attract many pieces of iron, sticking one to the other up to a large quantity, so many as it can bear.