Arrested in putsch, king has cause to breathe with difficulty (5)
I believe the answer is:
croup
'cause to breathe with difficulty' is the definition.
I can't tell whether this definition defines the answer.
'arrested in putsch king' is the wordplay.
'arrested in' indicates putting letters inside.
'putsch' becomes 'coup' (synonyms).
'king' becomes 'R' (abbreviation of Latin rex).
'coup' placed around 'r' is 'CROUP'.
'has' is the link.
Can you help me to learn more?
(Other definitions for croup that I've seen before include "Disease of the young with fever and breathing difficulty" , "Children's disease causing difficulty in breathing" , "Complaint of small children" , "Throat infection; horse's hindquarters" , "Rump of a horse" .)