niurt tréun is being translated to mighty power

niurt by itself is being translated to strength and tréun by itself is being translated to brave.

Is google translate sort of wonky or can somebody make sense of this for me?

I can make sense of it, yes, but then if you're not learning Irish, there's no reason to do so. Why don't you learn Irish from scratch?

Words have often more than one meaning. And Google translate, as any machine or human translator would do, tries to find out the best translation in context and interpretes sentences or phrases different to single words.

btw: I don't know whether "niurt" ever was a correct spelling in Irish.
Modern spelling is neart tréan

treun [no accent] is the Scottish Gaelic spelling. Not sure about niurt - might be an archaic spelling, but trean is used nowadays.

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I'm not a native (or entirely fluent) speaker, so be sure to wait for confirmations/corrections, especially for tattoos.

Google translate doesn't translate from one language to another one word at a time. Different languages have different word orders, so that would produce very poor translation. On top of that, it's sometimes necessary to find context clues for how to translate a particular word based on other words in a sentence. Google attempts to do this, and the result is that the more context you add, the more of the sentence you can provide, the more accurate the translation can be.



This looks like Old or Middle Irish to me. If so, Google translate cannot be expected to provide a reliable translation, as it is only intended to translate to and from Modern Irish. It is reasonably capable of handling some dialectal and pre-standard spelling variation, but Old and Middle Irish would be well beyond this scope.

Both words in Old Irish can be interpreted as o-stem nouns, but trén is generally treated as an adjective (see dil.ie). As individual nouns nert would mean strength or power, and trén would be a particular type of warrior, a strong-man. As an adjective, trén would mean "strong" or "powerful".

In the typical paradigm for Old Irish o-stem nouns in the dative case a u inflection would be expected, like we are seeing here. Because of spelling variation in Old Irish manuscripts it's impossible to say for any particular case whether or not the adjectival inflection required to make the adjective, trén, agree with the preceding noun would have caused the form to take a u. Regardless, forms like treúin and tríuin are certainly attested even where they break the typical paradigm of o-stems, eg. bad treúin iniriss "be ye strong in faith" (Wb. 27a6). I suspect OP has omitted some preceding text that would give us the context necessary to determine if this should be interpreted as the dative case or something else. If this hunch is correct, though, the translation probably should be "(to/from/by etc.) powerful strength".