Crack even parts to founder Titanic? (3-5)
I believe the answer is:
one-liner
'crack' is the definition.
(I've seen this before)
'even parts to founder titanic?' is the wordplay.
'even parts' means one should take alternating letters.
'titanic?' becomes 'liner' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The alternating letters of 'founder' are 'one'.
'one'+'liner'='ONE-LINER'
Can you help me to learn more?
(Other definitions for one-liner that I've seen before include "Quick joke?" , "Terse joke" , "Witty remark contained in a single sentence" , "Pithy joke" , "Witty remark consisting of a short sentence" .)