Seems like 'float' is the timespan between the order of a transaction by the customer (for example a money transfer), and the moment the money reaches the destined account. During this timespan, the money is moved to the bank's account, where it generates interest. this is how banks make their money :-)

Some alternatives to Harry's proposal:

* Seems like 'overboekingstijd' or 'overboekingstermijn' are commonly used in the Netherlands, but not so much in Flanders.

* A second alternative would be 'verwerkingstijd' or 'verwerkingstermijn'.

All of these terms have several hits on Google, so I guess it's safe to say there's room for creativity here :-)