Second royal in unpleasant house, a single-sex one (9)

I believe the answer is:

monastery

I'm a little stuck... Click here to teach me more about this clue!

'house a single-sex one' is the definition.
(where monks live without any women)

I can't explain the remainder of the clue.

Can you help me to learn more?

(Other definitions for monastery that I've seen before include "Residence of religious community" , "Religious house" , "Religious establishment" , "Community of monks" , "Where brothers gather" .)

I've seen this clue in The Guardian.

Want a hint initially instead of a full solution? Install my app