A Plastic Paddy is someone who claims to be Irish but never actually been to Ireland. Usually these people have a overly romantic view of Ireland. They are surprised when they go to Ireland and discover modern conveniences like shopping centres and WiFi.

They'll often try to claim to be related to a famous Irish king like Brian Boru as if it's something unique even though Brian Boru could potentially have over a million descendants.

They may ask Irish people abroad do they know "Thomas from Cork, or Mary from Kilkenny", as if Ireland is one giant village where everyone knows each other on a first name basis.

They call the Irish language "Gaelic" and often have misspelled tattoos in "Gaelic". It's not uncommon for plastic paddies to mistake elements of Scottish culture with Irish culture such as the wearing of kilts. Calling yourself "Irish" when you have only a modicum of Irish heritage may be way trying to justify your alcoholicism or enhancing your chances of becoming US president.
"That guy is such a plastic paddy, he kept talking to me about his families kilt pattern and I hadn't a fucking clue what he was talking about"
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