She has a flashy mate, a male in prison (6)
I believe the answer is:
peahen
'she has a flashy mate' is the definition.
I can't judge whether this definition defines the answer.
'a male in prison' is the wordplay.
'male' becomes 'he' (he refers to a man).
'in' means one lot of letters goes inside another.
'prison' becomes 'pen' (both can mean an enclosure).
'a'+'he'='ahe'
'ahe' put into 'pen' is 'PEAHEN'.
Can you help me to learn more?
(Other definitions for peahen that I've seen before include "Female bird (with a proud partner?)" , "Female of the large bird, Pavo species" , "one admiring male finery" , "Drab bird" , "Drabber female of a spectacular bird" .)