A thousand million years equals 1 billion years.
a millennium
One thousand years is a millennium, from the Latin "mille" for "thousand". One hundred years is a century, from the Latin "centum" for "hundred".
100 years is a "century."
the period after thousand is million ex, 1,200,030 the first comma says million the next comma says thousand
That's called a millenium.
A period of 1 thousand year is called a millennium.
A thousand million years equals 1 billion years.
a millennium
They happened over a period of two and a half thousand years. Which period did you have in mind?
A millennium is one thousand (1000) years.
One thousand years is a millennium, from the Latin "mille" for "thousand". One hundred years is a century, from the Latin "centum" for "hundred".
A millennium is a period of one thousand years.
millennium
A period of seven years is called a septennium.
generation
sevennenium