Dr Mac Coinnigh’s research examines phraseological units in the Irish language, primarily from a semantic, syntactic and lexical perspective. He has been involved in a major project in areal linguistics Widespread Idioms in Europe and Beyond, in which idiomatic and formulaic structures were mapped across a range of European languages.

In recent years his research focus has been in the field of Memory Studies where he has examined the relationship between language and conflict transformation. His current research project examines the links between (collective-cultural) memory, language and identity creation in post-conflict societies.