Crossword Genius

Can you connect with this form of humour? (10)

Ross

I believe the answer is:

lavatorial

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

'humour?' is the definition.
The definition and answer are not the same part of speech.

'can you connect with this form of' is the wordplay.
I cannot quite see how this works, but
'can' could be 'lav' (synonyms) and 'lav' is present in the answer.
'of' could be 'o' and 'o' is located in the answer.
The remaining letters 'atrial' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?

(Other definitions for lavatorial that I've seen before include "Such rude humour" , "(Of humour) rather vulgar" , "(Of humour) filthy" .)

I've seen this clue in The Guardian.
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