Toilet engaged? It looks serious (7)

I believe the answer is:

pofaced

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

'toilet engaged? it looks serious' is the definition.
I can't tell whether this definition defines the answer.

'toilet engaged?' is the wordplay.
'toilet' becomes 'po' (informal term for a chamber pot).
'engaged?' becomes 'faced' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'po'+'faced'='POFACED'

Can you help me to learn more?

(Another definition for pofaced that I've seen is " visibly disapproving".)

I've seen this clue in The Irish Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.