Definition of yellow plague in English:

yellow plague

noun

historical
  • An infectious disease with a high mortality rate occurring in sporadic epidemics, especially in Wales, England, and Ireland in the 6th and 7th centuries.

    No existing account of the disease provides enough information to identify it with certainty. Smallpox and relapsing fever have been suggested as likely candidates.

Origin

Mid 17th century; earliest use found in Hugh Paulinus Cressy (1605–1674), Benedictine monk.