US city rents in recession increase continually (6)
I believe the answer is:
spiral
'increase continually' is the definition.
(as in spiralling debts)
'us city rents in recession' is the wordplay.
'us city' becomes 'LA' (short for Los Angeles).
'rents' becomes 'rips' ('rip' can be a synonym of 'rent').
'in recession' shows that the letters should be reversed in order (letters recede or go back).
'la'+'rips'='larips'
'larips' written backwards gives 'SPIRAL'.
(Other definitions for spiral that I've seen before include "Shape of coil or helix" , "Mushroom" , "Shape of many galaxies" , "Corkscrew curve" , "Shape of a coiled spring" .)