Wife's at home, the husband's out and runs when it's cold (6)
I believe the answer is:
winter
'when it's cold' is the definition.
(the weather is cold in winter)
'wife's at home the husband's out and runs' is the wordplay.
'wife' becomes 'w'.
'at home' becomes 'in' ('I'm in' can mean 'I'm at home').
'the husband's out' becomes 'te' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'and' is a charade indicator (letters next to each other).
'runs' becomes 'r' (cricket abbreviation).
'w'+'in'+'te'+'r'='WINTER'
(Other definitions for winter that I've seen before include "period of discontent?" , "Cold period" , "period of freeze?" , "Coldest season" , "Time for mittens and scarves?" .)