A more literal translation might be 'there is no(thing) in/to them but lawyers', and thus 'they are only lawyers'. That's not super accurate, but it might get the meaning across.
I would suggest that "They are not only lawyers" could be "Ní hamháin gur dlíodóiri iad" ["Not only that are lawyers they"].
See this example from http://www.focloir.ie/ga/dictionary/ei/neighbour:
"they're not only our neighbours but also our friends - ní hamháin gur comharsana dúinn iad ach is iad ár gcairde freisin iad"
I don't know if this construction can, not only introduce an "ach" clause, as above, but also be used absolutely.
Someone else might be able to enlighten us further.
What about "They are nothing but lawyers?" To me that has the same meaning as "They are only lawyers" and is slightly closer to the Irish wording.
Can someone explain the use of the negative article even though there is no negative article in the sentence?
A literalish translation would be “There isn’t in them but lawyers” — the “not … but” structure is used to express the meaning of “only”, akin to “You ain’t nothing but a hound dog” meaning “You’re only a hound dog”.
Not that I know of — it was Leiber and Stoller who wrote the song, and I doubt that either of them spoke Irish.
Does the sentence in Irish potentially carry that same implication? that is, that they are "merely" lawyers and somehow limited as such? or is the Irish sentence no more than a factual observation that "all the members of that group of people happen to be lawyers"?
I tried the word "attorney" and it was marked as wrong. Is there a separate word for "attorney" vs. "lawyer"?
Hows about 'They are only but lawyers.' ? This is a common way of speaking where I am from but was wrong when I tried it. Thoughts?