What’s so different about Gweiadur?

Every word has a Welsh definition.
It contains idioms and compound words.
It provides Welsh/English equivalents and an English/Welsh glossary.
It is possible to change the language of the screen to English.


Where possible it standardizes noun gender;
It notes where gender differs between North and South Wales, e.g. munud;
It notes where a change of gender entails a change of meaning, e.g. ewyllys;
It notes where gender changes with the sex of the object, e.g. nyrs;
Plural forms are also included independently
These may be sought in all their mutated forms.


All inflected verbs are set down in their formal and informal registers in all tenses:

  • Present/Future
  • Past
  • Imperfect
  • Pluperfect
  • Imperative
  • Subjunctive

It lists the most common prepositions that follow the verb;
It gives English equivalents to the inflected tenses;
These may be sought in all their mutated forms.


Feminine and plural forms are listed;
Inflected forms are listed ‘cyn’ (wlyped) ‘yn’ (wlypach) ‘y’ (gwlypaf);
The location of the adjective (before or after that which it qualifies) is noted;
Any change of meaning resulting from changing its location is noted;
These may be sought in their mutated forms.

Sub-headings and Phrases

Many idioms and compound forms are listed.

Usage Notes

Many of the tips/quirks picked up in the process of compiling books on mutations, verbs, adjectives etc. have been included in the form a note.