### Clue: Almost understand case for drug (8)
### Answer: SEDATIVE 
 ### Explanation: Definition: drug
  SE(understand,see without its last letter,almost) DATIVE(in the grammar of certain languages such as Greek, German or Latin to denote the case of nouns, and adjectives used to express the indirect object, to identify the recipients, and for other purposes – regardless, it's all Greek to me 🙂