A Sikh on vacation engaged by, for instance, leisurely walk (6)
I believe the answer is:
sashay
'leisurely walk' is the definition.
(to sashay is to walk casually)
'a sikh on vacation engaged by for instance' is the wordplay.
'on vacation' says to hollow out the word (remove centre letters).
'engaged by' is an insertion indicator (I've seen this in other clues).
'for instance' becomes 'say' (both can be used to introduce an example).
'sikh' with its middle taken out is 'sh'.
'a'+'sh'='ash'
'ash' put into 'say' is 'SASHAY'.
(Other definitions for sashay that I've seen before include "Walk in showy way" , "Excursion" , "Casually move" , "Walk ostentatiously" , "Walk with exaggerated hip and shoulder movements" .)