Blessed heartless lady after laugh (4)
I believe the answer is:
holy
'blessed' is the definition.
(similar in meaning)
'heartless lady after laugh' is the wordplay.
'heartless' means to remove the middle letters.
'after' means one lot of letters go next to another.
'laugh' becomes 'ho' (representation of a laughing sound).
'lady' with its centre taken out is 'ly'.
'ly' put after 'ho' is 'HOLY'.
(Other definitions for holy that I've seen before include "Charlemagne was the first" , "Hallowed" , "Devout" , "Sacrosanct" , "Sanctified" .)