I am asking this question in the context of writing an academic paper. I am thinking if there exists a general rule regards to judging whether a compound adjective is colloquial, and, in this instance, specifically "top-of-the-line".
In my research area, the word "state-of-the-art" is commonly used. It seems colloquial to me, as it is composed of two words which do not really convey meaning, i.e. "of" and "the".
Now I am writing about a method being "top-of-the-line" among other baseline methods. I think the word's imagery works as the baselines can be considered as some line of products collectively; however, this compound adjective seems to suffer from the same problem mentioned above and convey ideas through imagery, here being "production line", just does not seem formal to me.
So, is there a general rule for what makes a compound adjective colloquial? I will list some traits in compound adjectives that worry me if I was to see them in formal writings:
- The compound adjective is too long (contains around 4 or more components).
- The compound adjective uses too many meaningless words, e.g. article, preposition, etc.
- The compound adjective can be replaced by some common adjectives.
Are my impressions bias from a non-native speaker?
Any suggestion or correction is appreciated.