1. Interjection (kandoushi)

   damn; damn it; shit; crap

   Usually written using kana alone

   お前の鼻をクソに擦りつけてやった。

2. Noun

   feces; excrement; dung

   ColloquialUsually written using kana alone

3. Prefix

   damn; damned; blasted; stupid

   Usually written using kana alone

4. very; extremely; really

   Usually written using kana alone

5. Na-adjective (keiyodoshi)

   terrible; awful; shit; crap

   ColloquialUsually written using kana alone

6. Adverb (fukushi)

   a lot

   SlangUsually written using kana alone

7. Noun

   negligible; insignificant; not mattering at all; counting for nothing; hardly worth consideration; out of the question

   Usually written using kana aloneas ...もくそもない or ...もくそもあるか

Also written 屎【くそ】