John pens 50 comments online? (4)
I believe the answer is:
blog
'comments online?' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.
'john pens 50' is the wordplay.
'john' becomes 'bog' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'pens' indicates putting letters inside.
'50' becomes 'l' ('L' can be a synonym of '50').
'bog' enclosing 'l' is 'BLOG'.
Can you help me to learn more?
(Other definitions for blog that I've seen before include "Internet journal" , "Online journal" , "published journal" , "Personal opinion website" , "Web diary" .)