Simple English definitions for legal terms
Read a random definition: half-tongue
Dereliction means leaving something or someone behind without taking care of them. It can be leaving your things somewhere and not coming back to get them, or not doing your job properly on purpose or by accident. If you don't do your job well and there's no good reason for it, that's called dereliction of duty.
Dereliction is when someone abandons something or fails to fulfill an obligation.
For instance, if a homeowner leaves their old car in their yard for years without using it or maintaining it, it becomes derelict. Anyone can come and take it because the owner has abandoned it. Similarly, if a police officer fails to perform their duties or does them poorly, they are guilty of dereliction of duty. This could include not responding to a call for help or not following proper procedures during an arrest.