Final answer:
Undruggable targets in drug discovery refer to targets for which no inhibitor has been found. These targets are difficult to target with drugs due to their lack of well-defined binding sites or complex structures. However, researchers are actively working to develop strategies and technologies to address this challenge.
Step-by-step explanation:
In drug discovery, the term undruggable refers to targets for which no inhibitor has been found. Undruggable targets are proteins or molecules that are difficult to target with drugs because they lack well-defined binding sites or have complex structures. Despite being challenging, researchers continue to explore innovative strategies and technologies to develop drugs that can effectively target undruggable proteins and molecules.