Day extremely full of disagreements, ready for bed (6)
I believe the answer is:
drowsy
'ready for bed' is the definition.
(I've seen this in another clue)
'day extremely full of disagreements' is the wordplay.
'extremely' says to hollow out the word (remove centre letters) (only the extremes of the word are used).
'full of' means one lot of letters goes inside another.
'disagreements' becomes 'rows' (row is a kind of disagreement).
'day' with its centre taken out is 'dy'.
'dy' placed around 'rows' is 'DROWSY'.
(Other definitions for drowsy that I've seen before include "Ready to sleep" , "Being rather tired" , "Dropping off" , "Half asleep" , "Sleepy, half-asleep" .)