a word or phrase that is used before another word to limit or add to its meaning

Cantonese requires the use of a premodifier, such as song fan, film fan, or football fan, to specify the type of fan someone is. 粤语需要使用前置修饰语比如歌迷、电影迷、或者足球迷来明确某人是哪种粉丝。

In "his own room" the word "own" is a pre-modifier of "room", not a post-modifier of "his". 在“his own room”这个词语中“own”是“room”的前置修饰语，而不是“his”的后置修饰语。