What is a group of 20 years called?

‘ So, 20 years = 2 Decades. 30 years = 3 Decades. 40 years = 4 Decades. 50 years = 5 Decades or Half a Century and so on.

What is a 50 year time period called?

A period of fifty years is called semi-centennial, Alternatively, if a period of ten years is called a decade, then fifty years could be called five decades, It is also half a century.

How many years make a century?

100 years
A century is a period of 100 years. Centuries are numbered ordinally in English and many other languages. The word century comes from the Latin centum, meaning one hundred.

What is after a millennium?

The answer is Eon. Eon often refers to a span of one billion years. Acccumulation is correct: the word myriad technically meant 10,000 and could be useful in 8,000 or so years.

What is every 30 years called?

Latin-derived numerical names

Anniversary	Latin-derived term	Other terms
30 years	Tricennial / Tricenary	Pearl jubilee
35 years	Quintricennial	Coral jubilee
40 years	Quadragennial / Quadragenary	Ruby jubilee
45 years	Quinquadragennial	Sapphire jubilee

What is a period of 12 years called?

Explanation: Duodecennial word can be used as alternatively for a gap once in 12 years .

What is the term for 1 million years?

A million years is called a megaannum, which is often abbreviated ‘Ma. ‘ This term comes from the word parts ‘mega’ which means ‘huge’ and ‘annum’…

What is 12 years called in English?

Latin-derived numerical names

Anniversary	Latin-derived term	Other terms
12 years	Duodecennial	Silk
12½ years	–	Parsley
13 years	Tredecennial	Lace
14 years	Quattuordecennial	Ivory