Buck maybe takes two seconds when rising on holiday (8)
I believe the answer is:
recessed
'on holiday' is the definition.
'buck maybe takes two seconds when rising' is the wordplay.
'two seconds' means two replacements for 'second'.
'buck maybe' becomes 'deer' (buck is a male deer).
'takes' indicates putting letters inside.
'second' becomes 's' (common abbreviation).
'second' becomes 'sec' (synonyms).
'when rising' says the letters should be written backwards.
's'+'sec'='ssec'
'deer' enclosing 'ssec' is 'dessecer'.
'dessecer' in reverse letter order is 'RECESSED'.
(Other definitions for recessed that I've seen before include "Adjourned or suspended" , "along the lines of bay" , "Set back in at wall" , "Set back by seceders" .)