What is the difference between どう and どういう? (e.g. どういう意味)


I'm researching the word 意味 (meaning/translation) and how to ask "What do you
mean?". It's translated as 「どういう意味？」and not 「どう意味？」. Why is it the former and
not the latter? Would the latter still be okay with a difference in
nuance/meaning?




[どう](https://dictionary.goo.ne.jp/word/%E3%81%A9%E3%81%86/#jn-154925) is an
adverb and
[どういう](https://dictionary.goo.ne.jp/word/%E3%81%A9%E3%81%86%E3%81%84%E3%81%86/#jn-154977)
is a 連体詞 which can come before a noun. Thus どう意味 is just ungrammatical.

For _what do you mean_ , you may be able to use どういうこと? as well.

