Dead tired? (3,2,6)
I believe the answer is:
out of breath
'tired?' is the definition.
('out of breath' can be similar in meaning to 'tired')
'dead' is the wordplay.
I cannot quite understand how this works, but
'dead' could be 'out' (similar in meaning) and 'out' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for out of breath that I've seen before include "Gasping" , "pants?" .)