Strong old labourer finally lifted chest (6)
I believe the answer is:
robust
'strong' is the definition.
(similar in meaning)
'old labourer finally lifted chest' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'finally' indicates one should take the final letters.
'lifted' shows that the letters should be reversed in order (going up in down clue).
'chest' becomes 'bust' (bust can mean a woman's chest).
The last letter of 'labourer' is 'r'.
'o'+'r'='or'
'or' in reverse letter order is 'ro'.
'ro'+'bust'='ROBUST'
(Other definitions for robust that I've seen before include "Sturdy and hardy" , "'Hearty, healthy (6)'" , "Physically strong" , "Strong and vigorous" , "Sturdy, resilient" .)