Hot swirling rapids conceal helmsman’s initial difficulty (8)
I believe the answer is:
hardship
'difficulty' is the definition.
(hardship is a kind of difficulty)
'hot swirling rapids conceal helmsman's initial' is the wordplay.
'hot' becomes 'h' (abbreviation eg on taps).
'swirling' indicates anagramming the letters.
'conceal' indicates putting letters inside.
'initial' says to take the initial letters.
The initial letter of 'helmsmans' is 'h'.
'rapids' with letters rearranged gives 'ardsip'.
'ardsip' going around 'h' is 'ardship'.
'h'+'ardship'='HARDSHIP'
(Other definitions for hardship that I've seen before include "Adversity, grimness" , "Lack of life's necessities, a tough time" , "Austerity - affliction" , "distress" , "Privation difficult to endure" .)