### Clue: Desert island loses border to east after short time (6)
### Answer: MOJAVE 
 ### Explanation: Definition: Desert
  JAVE{"Java",Indonesian island with "a",last letter,border **replaced by**(loses…to) "e",$$e$$ast} **placed after** (after) MO(short for moment,short period of time)
Answer:  The desert in south-west USA.