Toilet in the middle of street is quite inadequate (5)
I believe the answer is:
scant
'quite inadequate' is the definition.
'scant' can be an answer for 'inadequate' (I've seen this before). I am not sure about the 'quite' bit.
'toilet in the middle of street' is the wordplay.
'toilet' becomes 'can' ('can' can be a synonym of 'toilet'**).
'in the middle of' indicates putting letters inside.
'street' becomes 'st'.
'can' put within 'st' is 'SCANT'.
'is' acts as a link.
Can you help me to learn more?
(Other definitions for scant that I've seen before include "Little" , "Barely adequate" , "Barely sufficient" , "Bare" , "Reduce" .)