Funny press pitch — not regular (6)
I believe the answer is:
ironic
'funny' is the definition.
(I've seen this before)
'press pitch not regular' is the wordplay.
I cannot quite see how this works, but
'press' could be 'iron' (ironing is a kind of pressing) and 'iron' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for ironic that I've seen before include "Strange and perverse" , "Wryly funny" , "These words express the opposite of the literal meaning" , "Wry, sardonic" , "Mockingly humorous" .)