Mesmerized by Alexander Graham's weight, according to Spooner (10)
I believe the answer is:
spellbound
'mesmerized' is the definition.
(I know that mesmerized can be written as spellbound)
'alexander graham's weight according to spooner' is the wordplay.
I cannot really see how this works, but
'weight' could be 'lb' (lb is a kind of weight) and 'lb' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'by' is the link.
Can you help me to learn more?
(Other definitions for spellbound that I've seen before include "Enraptured" , "attending solidly" , "Transfixed, mesmerised" , "Entranced" , "Fascinated" .)