Ordinal Numbers and Fractions in Welsh

In Brief

Welsh uses cyntaf for “first”, ail for “second”, and gender-sensitive forms such as trydydd/trydedd for “third”. Word order is not uniform: compare y tro cyntaf “the first time” with yr ail dŷ “the second house”, where tŷ undergoes soft mutation. The most useful everyday fractions are hanner “half”, chwarter “quarter”, and traean “third”.

Overview

An ordinal number tells you an item’s position in an ordered series: first, second, third, and so on. Welsh ordinals appear in everyday phrases, instructions, dates, chapters, competition results, and names of historical periods. At B1, the goal is not merely to recite a list. You need to place an ordinal around a noun (a word naming a person, thing, or idea), choose a gendered form where necessary, and recognise the mutations that appear in the complete phrase.

Fractions describe parts of a whole. Welsh has short, frequent words such as hanner “half”, chwarter “quarter”, and traean “third”, as well as a transparent pattern using rhan “part”: dwy ran o dair, literally “two parts out of three”. These forms are useful when talking about time, food, measurements, groups, and percentages.

English-speaking learners need to watch two features in particular. First, English normally puts every ordinal before its noun, but Welsh commonly puts cyntaf after the noun while placing ail and several other ordinals before it. Second, the written beginning of a Welsh word may change through mutation. Learn yr ail dŷ, not simply ail + tŷ, so that word order and mutation become part of the same memory.

How It Works

The main ordinal forms

The forms from first to tenth are the essential working set. The abbreviations “m.” and “f.” below mean masculine and feminine grammatical gender: Welsh nouns belong to one of these two classes, and this can affect nearby words.

Position	Welsh	Main point
1st	cyntaf	Commonly follows its noun: y tro cyntaf
2nd	ail	Usually precedes its noun and causes soft mutation: yr ail dŷ
3rd	trydydd (m.), trydedd (f.)	Gender affects the form
4th	pedwerydd (m.), pedwaredd (f.)	Gender affects the form
5th	pumed	Usually precedes the noun
6th	chweched	Usually precedes the noun
7th	seithfed	Usually precedes the noun
8th	wythfed	Usually precedes the noun
9th	nawfed	Usually precedes the noun
10th	degfed	Usually precedes the noun

Do not try to derive all of these mechanically from the cardinal numbers you already know. Some are clearly related, but forms such as cyntaf, ail, and pumed are best learned as vocabulary.

“First” commonly follows the noun

A very productive pattern is:

y + noun + cyntaf

• y tro cyntaf — the first time
• y cam cyntaf — the first step
• y diwrnod cyntaf — the first day

After a feminine singular noun, an adjective (a describing word) commonly undergoes soft mutation. This gives phrases such as y wers gyntaf “the first lesson”: the base form cyntaf appears as gyntaf. The safest approach is to learn the whole phrase, because both the article and the noun’s gender contribute to what you see.

“Second” comes before the noun

Ail normally precedes the noun and triggers soft mutation, a regular change to the noun’s first consonant:

Base noun	After ail	English
tŷ	yr ail dŷ	the second house
car	yr ail gar	the second car
pennod	yr ail bennod	the second chapter
cwestiwn	yr ail gwestiwn	the second question
llyfr	yr ail lyfr	the second book

The article is yr here because ail begins with a vowel. Some nouns show no visible change because their initial sound has no applicable soft-mutated form, but the grammatical pattern is still the same.

Gender in “third” and “fourth”

The basic masculine and feminine pairs are:

Meaning	Masculine	Feminine
third	trydydd	trydedd
fourth	pedwerydd	pedwaredd

In a complete feminine phrase, mutation can affect both what the ordinal looks like and the following noun. Compare:

• y trydydd plentyn — the third child
• y drydedd wers — the third lesson
• y pedwerydd diwrnod — the fourth day
• y bedwaredd bennod — the fourth chapter

Here drydedd and bedwaredd are the mutated forms seen after the article in these feminine phrases. This is a good example of why dictionary forms alone are not enough. Memorise a short model phrase for each gender rather than applying an English-style “ordinal + noun” template.

Definite and stand-alone ordinals

The definite article corresponds to English “the”: y is used before most consonants and yr before a vowel. An ordinal can also stand alone when the omitted noun is obvious:

• y cyntaf — the first one / the person in first place
• yr ail — the second one
• y trydydd — the third one (masculine reference)

Context tells the listener whether this means a person, an answer, a prize, or another item.

Core fraction words

Fractions often behave as nouns or quantity expressions rather than as a single family of number endings.

Welsh	Meaning	Typical pattern
hanner	half	hanner awr — half an hour
chwarter	quarter	chwarter kilo — a quarter of a kilo
traean	a third	traean o’r dosbarth — a third of the class
rhan	part, share	dwy ran o dair — two thirds

With an indefinite unit or measurement, hanner and chwarter can go directly before the noun: hanner awr, chwarter litr. To identify a particular whole or group, Welsh often uses a definite phrase or o “of”: hanner y gacen “half the cake”, traean o’r bobl “a third of the people”.

Fractions with rhan ... o ...

The pattern number of parts + o + total number of parts makes the structure explicit:

• un rhan o dair — one third, literally “one part out of three”
• dwy ran o dair — two thirds
• tair rhan o bedair — three quarters

The words after o undergo soft mutation: tair becomes dair, and pedair becomes bedair. The forms also reflect the feminine noun rhan, so the feminine cardinals dwy, tair, and pedair appear. This pattern connects the present topic directly to basic Welsh numbers and mutation.

Examples in Context

Welsh	English	Note
Dyma’r tro cyntaf i mi ymweld â Chaerdydd.	This is my first time visiting Cardiff.	cyntaf follows tro.
Y cam cyntaf yw darllen y cyfarwyddiadau.	The first step is to read the instructions.	A common instructional phrase.
Enillodd hi’r wobr gyntaf.	She won first prize.	Feminine gwobr is followed by mutated gyntaf.
Mae e’n byw yn yr ail dŷ ar y chwith.	He lives in the second house on the left.	tŷ → dŷ after ail.
Darllenwch yr ail gwestiwn yn ofalus.	Read the second question carefully.	cwestiwn → gwestiwn.
Atebodd y trydydd plentyn y cwestiwn.	The third child answered the question.	Masculine form trydydd.
Bydd y drydedd wers yn dechrau am ddeg.	The third lesson will begin at ten.	Feminine phrase with drydedd.
Agorwch y bedwaredd bennod.	Open the fourth chapter.	Feminine phrase with bedwaredd.
Arhoson ni am hanner awr.	We waited for half an hour.	Direct quantity phrase.
Mae angen chwarter kilo o gaws.	A quarter of a kilo of cheese is needed.	Recipe or shopping quantity.
Bwytaodd hi hanner y gacen.	She ate half the cake.	A particular whole follows hanner.
Mae traean o’r dosbarth yn absennol heddiw.	A third of the class is absent today.	traean o introduces the group.
Mae dwy ran o dair o’r bobl yn cytuno.	Two thirds of the people agree.	Explicit rhan ... o ... fraction.
Mae hi’n chwarter wedi tri.	It is quarter past three.	Everyday clock time.
Mae hi’n chwarter i bedwar.	It is quarter to four.	i expresses the time remaining until four.

Common Mistakes

Putting cyntaf before every noun

• Wrong: y cyntaf tro
• Right: y tro cyntaf
• Why: Unlike English “first”, cyntaf very commonly follows the noun. Learn frequent expressions such as y tro cyntaf and y cam cyntaf as complete units.

Forgetting mutation after ail

• Wrong: yr ail tŷ
• Right: yr ail dŷ
• Why: Ail precedes the noun and normally causes soft mutation. The change is grammatical, not a different word for “house”.

Ignoring gender with “third” and “fourth”

• Wrong: y trydydd wers
• Right: y drydedd wers
• Why: Gwers “lesson” is feminine, so the feminine ordinal is needed; the full definite phrase also displays mutation. Contrast y trydydd plentyn.

Copying English fraction word order with o

• Wrong: hanner o awr
• Right: hanner awr
• Why: A simple indefinite measure normally follows hanner directly. Use o in patterns where it introduces a specified group or denominator, as in traean o’r dosbarth and dwy ran o dair.

Using masculine cardinals with rhan

• Wrong: dau ran o dri
• Right: dwy ran o dair
• Why: Rhan is feminine, so “two” is dwy. After o, tair undergoes soft mutation and appears as dair.

Usage Notes

The most frequent ordinals are often embedded in set expressions. Y tro cyntaf “the first time”, yr ail dro “the second time”, y cam cyntaf “the first step”, and y lle cyntaf “first place” are more useful in conversation than a memorised list of rare higher ordinals. Notice that tro cyntaf and ail dro use opposite word orders.

Short fractions are natural in speech, shopping, and recipes: hanner awr, chwarter kilo, hanner y pris “half the price”. The more analytical rhan ... o ... construction is especially useful when precision matters. In statistics, news, or formal explanations, you are more likely to encounter a fraction followed by a defined group, such as traean o’r boblogaeth “a third of the population”.

Clock expressions deserve to be learned separately. Chwarter wedi tri means “quarter past three”, while chwarter i bedwar means “quarter to four”. These are time-telling formulas; they do not establish a general rule for every kind of fraction.

Beyond the Basics

Higher ordinals occur in dates, centuries, official titles, school years, and formal numbering. Welsh has both decimal and traditional number patterns, so long ordinal expressions are not always predictable from English and may vary with context. Once you move beyond the first ten, confirm the conventional full phrase used for the date, century, or title rather than building it one word at a time.

Ordinals can be substantivised—that is, used as nouns when the actual noun is left unstated. Hi oedd y gyntaf can mean “She was the first,” while Fe oedd yr ail can mean “He was the second.” Mutation and gender may still be visible even though the noun has disappeared.

For mathematical work, you will encounter a wider range of specialised fraction terms and more elaborate expressions. Everyday hanner, chwarter, and traean remain important, but the rhan ... o ... pattern is a useful bridge because it states both the selected parts and the total clearly. Also distinguish a bare measurement, such as hanner litr, from part of a specified whole, such as hanner y dŵr “half the water”.

Practice Tips

1. Build phrase families. Choose one masculine and one feminine noun and make “first–fourth” sequences. For example, contrast y cam cyntaf, yr ail gam, y trydydd cam, y pedwerydd cam with a feminine series such as y wers gyntaf, yr ail wers, y drydedd wers, y bedwaredd wers.
2. Mark mutations in colour. Write the base and phrase together—tŷ → yr ail dŷ, cwestiwn → yr ail gwestiwn, tair → o dair—so you learn what triggered the change.
3. Use real quantities. Say the time, halve recipe quantities, or describe survey results aloud with hanner, chwarter, traean, and dwy ran o dair. Practical repetition makes the different fraction patterns easier to choose.

Related Concepts

• Prerequisite: Numbers — review cardinal forms such as dau/dwy, tri/tair, and pedwar/pedair, which support fraction phrases and gender agreement.