Several? Yes, ten! (3)
I believe the answer is:
six
'several? yes ten' is the definition.
The definition and answer can be both quantities as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'yes ten' is the wordplay.
'yes' becomes 'si' (I am not sure about this - if you are sure you should believe this answer much more).
'ten' becomes 'X' (Roman numeral).
'si'+'x'='SIX'
Can you help me to learn more?
(Other definitions for six that I've seen before include "Airborne boundary hit" , "Number of US moon landings" , "Number of bowls in a cricket over" , "VI" , "Half-dozen" .)