Fitter, but beginning to get more indolent (7)
I believe the answer is:
glazier
'fitter' is the definition.
(I've seen this before)
'beginning to get more indolent' is the wordplay.
'beginning to' suggests taking the first letters.
'more indolent' becomes 'lazier' ('lazy' can be a synonym of 'indolent').
The first letter of 'get' is 'g'.
'g'+'lazier'='GLAZIER'
'but' acts as a link.
(Other definitions for glazier that I've seen before include "Windowpane fitter" , "Worker with glass" , "Window mender" , "Skilled worker" , "Craftsman" .)