Six seconds matter for man of the house (8)
I believe the answer is:
viscount
'man of the house' is the definition.
(viscounts are members of the House of Lords)
'six seconds matter' is the wordplay.
'six' becomes 'VI' (Roman numerals).
'seconds' becomes 's'.
'matter' becomes 'count' (both can mean to be of significance).
'vi'+'s'+'count'='VISCOUNT'
'for' is the link.
(Other definitions for viscount that I've seen before include "British noble" , "Minor peer" , "Lord" , "British peer" , "Nobleman" .)