Expresses regret in a little footnote (5)
I believe the answer is:
weeps
'expresses regret' is the definition.
Although both the answer and definition are verbs in their -s form, I don't understand how they can define each other.
'a little footnote' is the wordplay.
'a little' becomes 'wee' (I've seen this before).
'footnote' becomes 'PS'.
'wee'+'ps'='WEEPS'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for weeps that I've seen before include "Sheds tears" , "Sobs" .)