讀音 vs. 語音

[ma3zi1]

If you have ever used the Taiwanese Ministry of Education online dictionary (國語辭典) you may have noticed some characters have two different possible pronunciations. One is called 讀音 and the other is called 語音.

I once asked a Taiwanese colleague of mine what the meaning of this distinction is, but (as often happens with native speakers) he basically didn't have a clue but still tried to convince me of some answer based on his own assumptions. What I mean is, he basically said, "I don't know what that means, but it's pronounced that way, not this way". Anyway, that didn't help me much. So here I am asking the question again: "What is the difference between 讀音 and 語音?"

Here is a list of examples for consideration:

鑿|凿

讀音：ㄗㄨㄛˋ zuo4

語音：ㄗㄠˊ zao2

白

讀音：ㄅㄛˊ bo2

語音：ㄅㄞˊ bai2

導|导

讀音：ㄉㄠˋ dao4

語音：ㄉㄠˇ dao3

耕

讀音：ㄍㄥ geng1

語音：ㄐ｜ㄥ jing1

Here are the definitions of 讀音 and 語音:

讀音 ＝ 1）字的唸法。2）國字在文言詞裡的讀法。

"1) The way to read a character aloud. 2) The method for reading characters when presented in Classical Chinese"

語音 ＝ 1）說話的聲音。2）字在口語中所念的音。相對於讀音而言。

"1) The sound when spoken. 2) The way a word is read colloquially, as opposed to 讀音"

Now, if it were as simple as picking 語音 (except in cases where we are speaking 文言文), then why is 耕種 pronounced "geng1 zhong4" and not "jing1 zhong4"? And, I know there are other examples of this... like why is 孔雀 pronounced "kong3 que4(讀音)" and not "kong3 qiao3(語音)"?

Is this just something I have to approach on a word-by-word basis? What about when two dictionaries don't agree? Like for example: 穿鑿附會 which is listed as "chuan1 zao2 fu4 hui4" in CC-CEDICT and "chuan1 zuo4 fu4 hui4" in 國語辭典. Is this as simple as mainland vs. Taiwan? Or, is there something more concrete that I'm missing?

[Hofmann]

Read this.

[ma3zi1]

That explains a lot, but I guess that means that the answer is that there is no concrete answer. For example, the Wikipedia articles says: "Some differences between the Taiwanese Guoyu and mainland Chinese Putonghua are due to one standard adopting a colloquial reading for a character while another standard adopts a literary reading."

So I guess it's all determined on a case-by-case basis?

By the way, I am assuming that 白讀 is the same as 語音, and 文讀 is the same as 讀音. Is that correct?

[Hofmann]

I think Guoyu tends to use more literary readings, but it is unpredictable.

I am assuming that 白讀 is the same as 語音, and 文讀 is the same as 讀音. Is that correct?

Yes.

[stonelee]

读音 means the pronunciation how to read out.

语音 usually it is a conversation.

[ma3zi1]

@stonelee, I'm sorry but your answer is very unclear to me. How is the pronunciation of a word different from the way it would be said during a conversation?