Empty tin can we are consistently failing to open (5)
I believe the answer is:
inane
'empty' is the definition.
(I've seen this before)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for inane that I've seen before include "Stupid and silly" , "Frivolous" , "Without meaning or point" , "Dull-witted" , "Foolish, silly" .)