Almost lean over, with a quantity of yielding (7)
I believe the answer is:
lissome
'yielding' is the definition.
(thesaurus)
'almost lean over with a quantity of' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'lean over' becomes 'list' (I've seen this before).
'with' says to put letters next to each other.
'a quantity of' becomes 'some' (I've seen this before).
'list' with its last letter taken off is 'lis'.
'lis'+'some'='LISSOME'
(Other definitions for lissome that I've seen before include "Willowy" , "flexible" , "So smile, being agile and lithe" , "Oil mess (anag)" , "Thin - supple - graceful" .)