Though lazy, I'd almost gone ahead (4)
I believe the answer is:
idle
'though lazy' is the definition.
'idle' can be an answer for 'lazy' (similar in meaning). I am unsure of the 'though' bit.
'i'd almost gone ahead' is the wordplay.
'i'd' becomes 'le' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'almost' means to remove the first letter.
'gone' becomes 'did' (doing is a kind of going).
'ahead' is a charade indicator (letters next to each other) (some letters go in front of others).
'did' with its first letter removed is 'id'.
'le' after 'id' is 'IDLE'.
Can you help me to learn more?
(Other definitions for idle that I've seen before include "Without work" , "Eric, perhaps" , "lndolent" , "goalless" , "Lazy - vain" .)