vigesimal

American  

[vahy-jes-uh-muhl] / vaɪˈdʒɛs ə məl /

adjective

1. of, relating to, or based on twenty.

2. twentieth.

3. proceeding by twenties.

---

vigesimal British  

/ vaɪˈdʒɛsɪməl /

adjective

1. relating to or based on the number 20

2. taking place or proceeding in intervals of 20

3. twentieth

---

Etymology

Origin of vigesimal

First recorded in 1650–60; from Latin vīgēsim(us), variant (with g of vīgintī “twenty”) of vīcēsimus, vīcēnsimus “twentieth” + -al ¹

Example Sentences

This may mean that the people who lived in what is now France used a base-20 or vigesimal number system.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

Numbers like seven and 31 belonged to all of these systems, quinary, decimal, and vigesimal alike.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

The only real difference was that instead of basing their numbers on 60 as the Babylonians did, the Mayans had a vigesimal, base-20 system that had the remnants of an earlier base-10 system in it.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

Europe yields one other example of vigesimal counting, in the number system of the Basques.

From The Number Concept Its Origin and Development by Conant, Levi Leonard

As the latter is due to finger-reckoning, so the use of the fingers and the toes produced a vigesimal scale.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 5 "Arculf" to "Armour, Philip" by Various