trillion
trillion /ˈtrɪljən/
adjective

One million million in the United States
(
trillion
)
one million million in the United States

One quintillion in Great Britain
(
trillion
)
one quintillion in Great Britain
noun

The number that is represented as a one followed by 12 zeros
(
1000000000000
, one million million
, trillion
)
the number that is represented as a one followed by 12 zeros
In England they call a trillion a billion
in England they call a trillion a billion

The number that is represented as a one followed by 18 zeros
(
one million million million
, trillion
)
the number that is represented as a one followed by 18 zeros
In England they call a quintillion a trillion
in England they call a quintillion a trillion

[Informal]
A very large indefinite number (usually hyperbole)
(
bazillion
[Informal, N. American] , billion
[Informal] , gazillion
[Informal] , jillion
[Informal, N. American] , million
[Informal] , trillion
[Informal] , zillion
[Informal] )
a very large indefinite number (usually hyperbole)
There were millions of flies
there were millions of flies