Mouse at home with dog in middle of settee (9)
I believe the answer is:
introvert
'mouse at home' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'with dog in middle of settee' is the wordplay.
'with' indicates putting letters inside.
'dog' becomes 'rover' (Rover is a common name for a pet dog).
'middle of' indicates the central letters.
The middle letters of 'settee' are 'tt'.
'in'+'tt'='intt'
'rover' put into 'intt' is 'INTROVERT'.
Can you help me to learn more?
(Other definitions for introvert that I've seen before include "Shy and reticent person" , "Reflective person" , "Turn inwards" , "Shy type" , "One who's withdrawn" .)