Sweet, sticky liquid from maple, possibly about a centilitre (7)
I believe the answer is:
treacle
'sweet sticky liquid' is the definition.
'treacle' can be an answer for 'liquid' (I have seen 'Viscous liquid ' mean 'treacle' so perhaps 'liquid' could also mean 'treacle'). I also know that 'sweet' relates to this answer.
'maple possibly about a centilitre' is the wordplay.
'maple possibly' becomes 'tree' (maple is a type of tree).
'about' means one lot of letters goes inside another.
'centilitre' becomes 'cl' (standard abbreviation).
'a'+'cl'='acl'
'tree' enclosing 'acl' is 'TREACLE'.
'from' is the link.
Can you help me to learn more?
(Other definitions for treacle that I've seen before include "Something cloyingly sweet" , "Contrived sentimentality - sticky substance" , "Thick syrup from sugar cane" , "Syrup, molasses" , "Electra (anag)" .)