A thing with no lid is hopeless (6)
I believe the answer is:
abject
'hopeless' is the definition.
(similar in meaning)
'a thing with no lid' is the wordplay.
'thing' becomes 'object' (I've seen this before).
'with no lid' means to remove the first letter (in a down clue, lid could mean the top letter).
'object' with its initial letter removed is 'bject'.
'a'+'bject'='ABJECT'
'is' acts as a link.
(Other definitions for abject that I've seen before include "Totally without dignity" , "woeful" , "Down-hearted" , "Low in spirit or hope" , "Without pride or dignity, self-abasing" .)