n
a)[C]
when money is moved from one bank account or investment to another without any tax or other fees having to be paid
　Many CD rollovers happen in October.
b) [U and C]
the action of making a bank account, investment etc do this
rollover of
　The law allows a rollover of retirement money from a company pension to an IRA.
[C]BrE
if there is a rollover in a competition or lottery, nobody wins the biggest prize that week, and the money is added to the prize that can be won the following week
[C]
an accident in which a car turns over onto its roof
[U]technical
a way of making the images change whenever someone using a mouse moves it over a particular word or picture on a computer screen