Otherwise detains (7)
I believe the answer is:
instead
'otherwise detains' is the definition.
I can't judge whether this definition defines the answer.
'otherwise detains' is the wordplay.
'otherwise' is an anagram indicator.
'detains' is an anagram of 'INSTEAD'.
Can you help me to learn more?
(Other definitions for instead that I've seen before include "use this as a replacement" , "In place (of)" , "Alternatively" , "as an alternative option" , "As a substitute" .)