On page 235 of the first volume of Daniel Block's commentary on Ezekiel, Block says:
Ezekiel is also ordered to utter the interjection Ah! (’āׅh). This form of the onomatopoeic paralinguistic utterance...
My mommy taught me what onomatopoeic was with words like hoopoe and cuckoo (though in the second case she used a foreign language which does a better job of approximating the bird's actual sound), but I'm not sure what it means in this context, or how a sound can be onomatopoeic for an emotion. Certainly, in all the languages I know, "ach" is an expression of intense emotion and seems intuitively correct in a way that a word like, say, "bird", never could.
But I don't know how to formalize exactly how this interjection is onomatopoeic according to my understanding of the word, and I'm not sure that my own sense of "intuitive correctness" means anything.
Is Block stretching the use of this word, or is this a standard use of it in linguistics? Specifically, can onomatopoeia ever refer to a word formed for an entity which does not inherently have a specific aural association?