Just as you have used various English suffixes to turn nouns into adjectives ("-ly", "-ish", "-ful", ...), there are a number of ways to do this in Japanese, too. Most important ones are:
損 (disadvantage) / 損な (disadvantageous)
不思議 (mystery, wonder) / 不思議な (mysterious)
真 (truth) / 真の (true)
永遠 (eternity) / 永遠の (eternal)
子供 (child) / 子供っぽい (...
Take a step back for a second. I think you need to stop thinking of Kanji as words and start thinking of Kanji as letters which make sounds which you use to spell words.
Kanji don't have any meaning without context, just like letters. Some kanji only make one sound and some kanji can make multiple sounds depending on the context. Think about the letter 'G' ...