If a word or a name is pronounceable, you can say it out loud without much trouble. Your mouth can make the sounds, and other people can hear it as a real word. Teachers use this a lot with names from other languages: some names feel easy for English speakers, and some do not. Though actually, “easy” depends on who is talking — a name that feels hard in English may be perfectly easy in another language. People also stretch it a little for invented words, brand names, and passwords. The opposite is unpronounceable, which speakers sometimes say, not very kindly, about a word they cannot get their tongue around. It is an ordinary, slightly school-like word, not slang and not very formal.

好念的、唸得出來的