Adjective
unenriched (not comparable)
Not enriched.
By merely placing cheap unenriched uranium into such a core, the non-fissionable U-238 will be turned into Pu-239, "breeding" fuel. Source: Internet
The material was unenriched and so could not be used to build a conventional fission bomb, but a dirty bomb is a theoretical possibility. Source: Internet
Nuclear pollution On 8 July 2008 waste containing unenriched uranium leaked into two rivers from a nuclear plant in southern France. Source: Internet