Note. Question on one new animal for an annual occasion (7)
I believe the answer is:
equinox
'an annual occasion' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'note question on one new animal' is the wordplay.
'note' becomes 'e' (musical note).
'question' becomes 'qu' (abbreviation).
'on one' becomes 'i' (Roman numeral. I am not sure about the 'on' bit.).
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'animal' becomes 'ox' (castrated bull).
'e'+'qu'+'i'+'n'+'ox'='EQUINOX'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for equinox that I've seen before include "it occurs twice a year" , "Day with 12 hours of light" , "When the sun crosses the equator" , "Spring or autumn festival" , "Time of day/night equality" .)