When Pams indisposed in the ship, convulsions result (6)
I believe the answer is:
spasms
'the ship convulsions result' is the definition.
I can't tell whether this definition defines the answer.
'when pams indisposed in' is the wordplay.
'when' becomes 'ss' (I am not sure about this - if you are sure you should believe this answer much more).
'indisposed' indicates an anagram.
'in' is an insertion indicator.
'pams' is an anagram of 'pasm'.
'ss' enclosing 'pasm' is 'SPASMS'.
Can you help me to learn more?
(Other definitions for spasms that I've seen before include "sudden bursts of activity" , "Sudden convulsions" , "Involuntary convulsive movements" , "Convulsions, fits" , "Uncontrollable muscle contractions" .)