Many turning up lazily and impassively (8)
I believe the answer is:
stolidly
'impassively' is the definition.
(stolid can mean impassive or calm)
'many turning up lazily' is the wordplay.
'many' becomes 'lots' (lots of something).
'turning up' says the letters should be written in reverse.
'lazily' becomes 'idly' (synonyms).
'lots' in reverse letter order is 'stol'.
'stol'+'idly'='STOLIDLY'
'and' is the link.
(Other definitions for stolidly that I've seen before include "Impassively" , "In unemotional manner" , "In an impassive manner" , "Without feeling" , "Showing no interest" .)