Proclaim one-time fortune turning up (5)
I believe the answer is:
extol
'proclaim' is the definition.
('extol' can be a synonym of 'proclaim')
'one-time fortune turning up' is the wordplay.
'one-time' becomes 'ex'.
'fortune' becomes 'lot' ('lot' can be a synonym of 'fortune').
'turning up' shows that the letters should be reversed in order.
'lot' in reverse letter order is 'tol'.
'ex'+'tol'='EXTOL'
(Other definitions for extol that I've seen before include "Lift up" , "celebrate" , "Acclaim" , "Lavishly praise" , "Praise highly, laud" .)