Entrance Lords with the smashing, captivating hundred on debut (9)
I believe the answer is:
threshold
'entrance' is the definition.
(I've seen this before)
'lords with the smashing captivating hundred on debut' is the wordplay.
I cannot really see how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found in the answer.
'on' could be 're' ('on' can be mean 'with reference to') and 're' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for threshold that I've seen before include "Point of entry" , "gate" , "Lower limit" , "Verge" , "Doorstep" .)