Regularly relax by taking the top off (5)
I believe the answer is:
often
'regularly' is the definition.
(often means regularly or frequently)
'relax by taking the top off' is the wordplay.
I cannot really see how this works, but
'by' could be 'of' and 'of' is present in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found within the answer.
The remaining letters 'en' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for often that I've seen before include "Multiply" , "In many cases" , "More than occasionally" , "Commonly" , "A great deal" .)