Piece of yarn earl yanked, just about (6)
I believe the answer is:
nearly
'just about' is the definition.
(synonyms)
'piece of yarn earl yanked' is the wordplay.
'piece of' indicates a hidden word.
'NEARLY' can be found hidden inside 'yarn earl yanked'.
(Other definitions for nearly that I've seen before include "Almost, well-nigh" , "Almost, not quite" , "More or less" , "parsimoniously" , "Give out a bright light" .)