sevennenium
It has no individual name
generation
100 years is a "century."
term millennium
A decade.
about 7 years
If I remember right its 7 years
The customary period now is 7 years.
Its called a century! century means 100 years and decade means 10 years
A period of 100 years is called a century. For example, the 20th century refers to the years from 1901 to 2000. Additionally, a period of 1,000 years is referred to as a millennium.
That's called a millenium.
A period of 25 years is called a "quarter century." This term is often used to refer to significant milestones or anniversaries that occur every 25 years.