Numbers index

Words for numbers in English


Words for numbers --- English --- French and German --- Songs --- Counting sheep


English words for numbers

When learning about numbers, it's easy just to think about the number symbols. But numbers can be described as words as well. We learn these words as children, or even babies, long before we meet our 1,2,3. Enter a number to see what the words are, or click on Count numbers. It will work up to the trillions.

Enter number:      every
 

We use these words when we talk of numbers, unless we are describing a long number, like a telephone number. Even then, we use the words for the digits. However, if we write numbers, we usually use the symbols instead. There is one exception. Cheques are written using words as well as numbers. Numbers can be altered quite easily. Words are harder!

If this was a number system, then it wouldn't be unary or positional. You might think it was positional, as the same numbers get used no matter how large the number is. You say two thousand and two. But you need the word thousand to tell you how big the first two is. There is a word for zero, but you don't use it inside a number. For example, you don't say two thousand, zero hundreds, zero tens and two.


Prefixes

A prefix is part of a word, at the front. There are prefixes which describe numbers. For example, a hemisphere is half a sphere. There is more than one prefix for each number as they come from different languages (usually Latin or Greek), or they are spelled different ways in different words.

Semi, hemi, demi1/2
Uni1
Bi, di2
Tri, ter3
Tetra, tetr, tessera, quadri, quadr4
Pent, penta, quinqu, quinque, quint5
Sex, sexi, hex, hexa6
Hept, hepta, sept, septi, septam7
Oct, octa, octo8
Non, nona, ennea9
Dec, deca10
Hendca, undec, undeca11
Dodeca12
Trideca13
Quindeca15
Icos, icosa, icosi20

Incidentally, the irrational fear of the number 13 is Triskaidekaphobia which comes from the Greek tris (three) + kai (and) + deka (ten).


Special words for numbers

Some numbers have special words.

2a couple In metric measurement, the most important number is ten. But in Imperial Measures, many other numbers were important. Every British school child used to know that there were twelve inches in a foot. Before 1971, even the British money was different, and there were twelve old pennies in a shilling, and twenty shillings in a pound. So you can see that twelve (or a dozen) and twenty (or a score) were important numbers.
2a pair
2a brace
6half a dozen
12a dozen
13a baker's dozen The baker's dozen was so-called because a baker used to give an extra roll if you asked for a dozen. The reason was to prevent being prosecuted for short weight. Bread was the staple diet in England in mediaeval times and had to be a certain weight. It is difficult to bake bread to a particular weight, so when a person ordered a dozen the thirteenth loaf was added to make sure it was not underweight.
20a score
144a gross (12 dozen)
1728a great gross (12 gross)

Special words for numbers of people

Group of musicians
or singers
Number of people
Soloist1
Duet2
Trio3
Quartet4
Quintet5
Sextet6
Septet7
Octet8
Siblings born togetherNumber of people
Twins2
Triplets3
Quadruplets or Quads4
Quintuplets or Quins5
Sextuplets6

Big number words

British English and American English used to have different meanings for 'billion' and 'trillion'. The British used to use a billion to mean a million million and a trillion to mean a million million million but now they use these words in the same way as the Americans. A billion is a thousand million or 1,000,000,000. A trillion is a million million, or 1,000,000,000,000.

Children often invent words for 'really big numbers'. These don't have a standardised size, they are just indicating an enormous number. When I was young, we used zillion. Now, British children seem to use squillion or gazillion instead.


Powers of ten

The metric system has a regular system of prefixes to describe the units. For example, a hundreth of a metre is a cetimetre, and a thousand metres is a kilometre.

Multiples

PrefixSymbolValuePower of ten
TeraT1,000,000,000,0001012
GigaG1,000,000,000109
MegaM1,000,000106
Kilok1,000103
Hect, hectoh100102
Dec, decaD1010

Fractions

decid0.110-1
Centic0.0110-2
Millim0.00110-3
Microµ0.00000110-6
Nanon0.00000000110-9
Picop0.00000000000110-12
Femtof0.00000000000000110-15
Attoa0.00000000000000000110-18

Alphabetical order of number words

These numbers are in a particular order. What is it?

8, 5, 4, 9, 1, 7, 6, 3, 2

The clue is in the heading. If you write the words for these numbers, they're in alphabetical order: eight, five, four, nine, one, seven, six, three, two.

Now imagine that the words for every single number is listed in alphabetical order. This is rather hard, as there are an infinite number of them! But if we did, what would the first word be? Eight. And the last would be zero!