Type of sleep those with no ambition experience (9)
I believe the answer is:
dreamless
'type of sleep' is the definition.
'dreamless' can be an answer for 'sleep' (I have seen 'such sleep' mean 'dreamless' so perhaps 'sleep' could also mean 'dreamless'). I am not certain of the 'type of' bit.
'those with no ambition experience' is the wordplay.
I cannot really see how this works, but
'ambition' could be 'dream' (synonyms) and 'dream' is present in the answer.
The remaining letters 'less' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for dreamless that I've seen before include "such sound sleep?" , "Lacking aspiration" , "So deep in sleep" , "Lacking any vision" .)