Stupid and boring to have doctor and engineer together (8)
I believe the answer is:
dumbbell
'stupid' is the definition.
(thesaurus)
'boring to have doctor and engineer together' is the wordplay.
'boring' becomes 'dull' (similar in meaning).
'to have' is an insertion indicator.
'doctor' becomes 'mb' (Bachelor of Medicine, Medicinae Baccalaureus).
'and' is a charade indicator (letters next to each other).
'engineer together' becomes 'be' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'mb'+'be'='mbbe'
'dull' enclosing 'mbbe' is 'DUMBBELL'.
'and' is the link.
Can you help me to learn more?
(Other definitions for dumbbell that I've seen before include "Short bar with weights for exercising (4-4)" , "Exercising weight" , "Weightlifter's item" , "Bar with weighted ends used in exercising" , "Weight-training equipment" .)