Recently a new site has been set up in which there is a dictionary, a glossary and a thesaurus containing a vast quantity of words. It can be found at:
This site was designed by Michal Boleslav Mechura, and it is very useful for those writing in Irish. It effectively reduces word search time in many instances.
Potafocal.com is a collection of dictionaries and databases in Irish. It acts as a dictionary, glossary, thesaurus based on this as well as an indicator of word frequency. There is usually an ample selection of examples to go with any word picked.
The site is very useful when a particular word is being sought.