I'm trying to use the correct translation of "to shirk."
In the Foclór Gaelige—Béarla dictionary, it lists "leiciméireacht" as the word, but I haven't yet found that word elsewhere. Is there a more fitting word that should be used in its stead, or is this one alright but just uncommon?

Thank you in advance!

LJCesco, you generally get more sense out of the focloir.ie dictionary. See https://www.focloir.ie/en/dictionary/ei/shirk for example.

English Irish Dictionary (de Bhaldraithe)
https://www.teanglann.ie/ga/eid/shirk
Foclóir Gaeilge-Béarla (Ó Dhónaill)
https://www.teanglann.ie/ga/fgb/shirk
Foclóir Nua Béarla-Gaeilge
https://www.focloir.ie/ga/dictionary/ei/shirk

I’d use loic (vn. loiceadh)
https://www.teanglann.ie/ga/fgb/loic

The word leiciméireacht, which I was not previously aware of, is in use, in that Nua-Chorpas na hÉíreann contains instances of modern use. However, the corpus extends to 30m words of text, with leiciméireacht only used 12 times. This means it occurs 0.4 times per million words of text. This is effectively a rare word. The Russian Frequency Dictionary recommends that learners of Russian only need to learn words as frequent as those occurring 10 times per 1m words to be proficient in Russian, and that all other words are pointless for a learner (although that dictionary rounds out 10,000 words by including words with a frequency of 8 times per 1m). You could easily be fluent in Irish and not know this word.

Edit: loic and words beginning with loic (loiceann, loicfidh, etc) occur 301 times in the Nua-Chorpas, roughly 10 times per million words, which, if you accept that in any language a word that occurs 8-10 times or more per milllion needs to be learnt by learners to be proficient, is just about in that category.

to shirk - meaning to avoid responsibility or duty.

https://www.teanglann.ie/en/eid/shirk
Seachnaím (obair, dualgas); déanaim faillí i (ndualgas). Abs. Loicim.

Seachnaím - I avoid
Loicim = I fail

Déanaim faillí... I neglect.... = I think this is the closest meaning.
Rinne sé faillí ina chuid oibre. - He neglected/shirked his work.

If you give us a sentence we'll be able to say it better.

Thank you for all of the input so far! (And apologies for tossing in such an uncommon word.)

Along the lines of the full sentence that I am hoping to translate would be something that I say all the time because I'm a bit of a weirdo XD

"We don't want to/wouldn't want to be shirking" or "Let's not be shirking," etc.

I know that not every tense and mood in English can be directly translated and make sense/sound normal in other languages, so I would be very grateful to learn the translation for whatever would sound natural for Irish Gaelic speakers.
Again, it's a little funky, but I say that word jokingly all the time, so aiming to use it for some dialogue in a sequel.

It's interesting, as I generally tell people to avoid foclóir unless the entry doesn't exist in Teanglann. This is because foclóir's corpus is, to put it plainly, not all that great. It doesn't collect solely native examples, and has a lot of non-native stuff. Sometimes, only non-native stuff is used for a turn of the phrase. I can't remember it now, but I remember using one of those with a friend of mine from Carraroe, and he said he could only understand it by directly translating it to English first, and then gave me a more natural Irish way to say it which was not on foclóir. It's better if you have corpus access, but I also know of at least one non-native who claims to be native and is thus listed that way in the corpus. And, of course, they don't, unfortunately, let you filter by 'Gaeltacht native' versus 'Non-Gaeltacht native'.

I meant in terms of the fact that focloir.ie has a lot of "US colloquialisms" - i.e. very up-to-date English that you can search for. The Irish is a mixed bag. As you say, including non-natives as natives contradicts the very principles of linguistic scholarship. A non-Gaeltacht native - is not really a native speaker at all. Are there any Dublin-based native speakers of Chinese, Hindi, etc? Presumably there are some who claim to be so, but they won't speak like people in China and India. Have you seen videos of Rami Malek being interviewed by an Egyptian and speaking in Arabic for some of the interview (on Youtube)? It is clear that, although Arabic was his first language, growing up in the US has not given him native-equivalent skills, and for most of the interview had to speak in English instead.... Add to that the fact the parents of "native Irish speakers" in Dublin spoke poor Irish to begin with, and the whole thing is a farce. Even some genuine native speakers in the corpus will have looked up many words on teanglann, and so books by Gaeltacht natives are generally NOT written in the language of the tigh tábhairne....

Thank you for all of the information, everyone!