Emotional moment interrupted by short buzzer (8)
I believe the answer is:
poignant
'emotional' is the definition.
(thesaurus)
'moment interrupted by short buzzer' is the wordplay.
'moment' becomes 'point' (a point in time).
'interrupted by' means one lot of letters goes inside another.
'short buzzer' becomes 'gna' (I can't justify this - if you can you should give a lot more credence to this answer).
'point' going around 'gna' is 'POIGNANT'.
Can you help me to learn more?
(Other definitions for poignant that I've seen before include "Moving, touching" , "Evoking sadness or regret" , "Arousing sympathy, moving to the feelings" , "Sharply upsetting" , "Distressing" .)