Leave club in cab — sail out! (10)
I believe the answer is:
sabbatical
'leave' is the definition.
(sabbatical is a kind of leave)
'club in cab sail out' is the wordplay.
'club' becomes 'bat' (bat is a kind of club).
'in' indicates putting letters inside.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'cab'+'sail'='cabsail'
'cabsail' anagrammed gives 'sabical'.
'bat' inserted within 'sabical' is 'SABBATICAL'.
(Other definitions for sabbatical that I've seen before include "Academic period of paid leave" , "Period of leave for university teacher" .)