Why do the readings change?

Question

Forgive my title as I don’t really have a good one at the top of my head.

I’ve always been into word play when it comes to naming characters, but when it comes to Japanese it’s kinda difficult for me. I’ll put together a word that I think means one thing and it completely translates into something different.

Ex: Kōaki- Kō(孝) Filial piety and Aki(彰) Clearly but when it but when I put the two together it’s Takaaki.

Is there something that I’m misunderstanding?

Answer 1

I'm not entirely sure I understand your question, but for the record:

1. Due to the way the Japanese writing system evolved, the same kanji can have many different readings, including onyomi (Chinese origin) and kunyomi (Japanese origin).
2. Usually the way a kanji is read is determined by its context within a sentence or what kanji it is paired with, but with names there are less rules. In particular, onyomi and kunyomi are usually not mixed within the same word, but it can occur in names.
3. A kanji's reading and its meaning are entirely separate. Just because a kanji reads differently in different contexts doesn't mean the meaning is different. Vice versa, the same reading can have multiple meanings.

As an example, the following kanji has 11 possible readings when placed inside a name. When you make a Japanese name, you have to choose both the kanji and a corresponding reading.

Answer 2

孝 read as こう is an 音読{おんよ}み, which is to say it's derived from Chinese. 彰 read as あき is a 訓読{くんよ}み, coming from a native Japanese word. (Actually it's a 名乗{なの}り, meaning it's only used in names, but AFAIK the distinction doesn't matter here.) Mixing the two in one word is unusual — but certainly not unheard of, especially in names, so you should be fine reading it as こうあき.