Bubonic plague (5,5)
'bubonic plague' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for pestilence that I've seen before include "dire horseman?" , "Plague - lent pieces (anag)" , "it's an agent of evil" , "Deadly epidemic disease" , "morally harmful influence" .)
'bubonic plague' is the definition.
(Black Death is an example)
This is the entire clue.
(Other definitions for black death that I've seen before include "Great 14th-century killer epidemic" , "Disease" , "14th century plague" , "Bubonic plague epidemic" , "Fourteenth.-cent. plague" .)