Traditional Numbers: un ar ddeg, ugain
Traditional Counting in Twenties
Next to modern counting (un deg un, dau ddeg), Welsh has an older system built on twenty. It is very much alive in times, ages and dates.
How It Works
11 to 20
- 11 un ar ddeg, 12 deuddeg, 13 tri ar ddeg (with a feminine noun tair ar ddeg), 14 pedwar ar ddeg (feminine pedair ar ddeg)
- 15 pymtheg, 16 un ar bymtheg, 17 dau ar bymtheg (feminine dwy ar bymtheg), 18 deunaw (literally "two nines"), 19 pedwar ar bymtheg (feminine pedair ar bymtheg)
- 20 ugain
21 to 60
- 21 un ar hugain, 22 dau ar hugain, 25 pump ar hugain, 30 deg ar hugain, 35 pymtheg ar hugain
- 40 deugain, 50 hanner cant ("half a hundred"), 60 trigain
Small sound changes. After ar, deg and pymtheg soften to ddeg and bymtheg, and ugain always becomes hugain. The h is fixed in this number, like the h in Adding H Before Vowels.
Where does the noun go? The noun comes straight after the first number word and stays singular: un tŷ ar ddeg (eleven houses), pum munud ar hugain (twenty-five minutes), tair merch ar ddeg (thirteen girls). Before blynedd, blwydd and diwrnod, some numbers change shape and cause nasal mutation: see blynedd and blwydd after numbers.
Where you will meet it
- Clock times: ugain munud wedi tri, pum munud ar hugain i bump. See Telling the Time.
- Ages: Mae hi'n un ar hugain oed. See Saying Your Age.
- Dates: y pumed ar hugain o Ragfyr. See Dates.
- Older speakers, poems, hymns and older books.
Both systems are correct Welsh. Modern counting is handy for big numbers, prices and maths; the traditional words sound most natural for time and age. Many people mix the two.
Examples (5)
- Bydd fy mrawd yn un ar hugain oed fis nesaf.
My brother will be twenty-one next month.
- Mae'r ffilm yn dechrau am ugain munud wedi wyth.
The film starts at twenty past eight.
- Mae hi'n bum munud ar hugain wedi un.
It's twenty-five past one.
Pum softens to bum after yn, and the noun munud sits between pum and ar hugain.
- Mae un tŷ ar ddeg yn y stryd.
There are eleven houses in the street.
The singular noun tŷ goes after the first word, un.
- Mae fy nhad yn drigain oed.
My father is sixty.
Trigain softens to drigain after yn.
Common Mistakes
Leaving the h off hugain.
Mae hi'n un ar ugain oed.Mae hi'n un ar hugain oed.After ar, ugain always becomes hugain: un ar hugain, deg ar hugain.
Putting the noun after the whole number.
un ar ddeg tŷun tŷ ar ddegIn the traditional system the noun follows the first number word: un tŷ ar ddeg, pum munud ar hugain.
How It Connects
Learn This First
Traditional counting in twenties is a second number system.
Related Patterns
- Faint o'r gloch?Telling the Time
Clock times use the traditional numbers.
Level 2 - oed: Saying Your AgeSaying Your Age
Ages are often said with traditional numbers.
Level 2 - blynedd / blwydd After NumbersYears and Age After Numbers
Special number forms and nasal mutation before years and days.
Level 4 - Dates: y cyntaf o FawrthDates
Dates such as y pumed ar hugain use the same pattern.
Level 3 - tri / tair, pedwar / pedairFeminine Three and Four
Feminine tair and pedair also appear inside 13, 14 and 19.
Level 2
Words in This Pattern
Practice Traditional Numbers: un ar ddeg, ugain in Bubblegum
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