Picked up hot hint about a Parisian castrato? (6)
I believe the answer is:
eunuch
'a parisian castrato?' is the definition.
The definition suggests a singular noun which matches the answer.
'picked up hot hint about' is the wordplay.
'picked' becomes 'un' (I can't explain this - if you can you should give a lot more credence to this answer).
'up' is a reversal indicator (in down clue: letters go upwards).
'hot' becomes 'h' (abbreviation eg on taps).
'hint' becomes 'cue' (cue can mean a hint or prompt).
'about' means one lot of letters goes inside another.
'h'+'cue'='hcue'
'hcue' reversed gives 'euch'.
'un' inserted inside 'euch' is 'EUNUCH'.
Can you help me to learn more?
(Other definitions for eunuch that I've seen before include "Unsexed male guardian in harems" , "Typical harem guard" , "Castrated person" , "Harem guard specially cut out for the job" , "One deprived of his masculinity?" .)