Doctor left it after working under night-time conditions? (7)
I believe the answer is:
moonlit
'doctor left it after working under night-time conditions?' is the definition.
I can't judge whether this definition defines the answer.
'left it after working under night-time conditions?' is the wordplay.
'left' becomes 'l' (common abbreviation).
'after' says to put letters next to each other.
'working under night-time conditions?' becomes 'moon' (I can't justify this - if you can you should give a lot more credence to this answer).
'l'+'it'='lit'
'lit' after 'moon' is 'MOONLIT'.
Can you help me to learn more?
(Other definitions for moonlit that I've seen before include "like the bank Jessica used?" , "like Titania's unlucky meeting" , "Illumined by Selene?" , "Illuminated by night" , "Illuminated by satellite" .)