Late boss, a dull, uninspiring person (8)
I believe the answer is:
deadhead
'a dull uninspiring person' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'late boss' is the wordplay.
'late' becomes 'dead' (similar in meaning).
'boss' becomes 'head' (synonyms).
'dead'+'head'='DEADHEAD'
Can you help me to learn more?
(Other definitions for deadhead that I've seen before include "Remove faded blooms from" , "archetypal hippy" , "Trim faded bloom" , "bore" , "One doesn't pay to get in" .)