Overwhelm head constable interrupting dinner (7)
I believe the answer is:
scupper
'overwhelm' is the definition.
The answer and definition can be both to do with communicating as well as being verbs in their base form.
Maybe you can see a link between them that I can't see?
'head constable interrupting dinner' is the wordplay.
'head' says to take the initial letters.
'interrupting' means one lot of letters goes inside another.
'dinner' becomes 'supper' (synonyms).
The initial letter of 'constable' is 'c'.
'c' placed inside 'supper' is 'SCUPPER'.
Can you help me to learn more?
(Other definitions for scupper that I've seen before include "dish" , "Ruin (plans)" , "Thwart" , "Sink one's own ship deliberately" , "hole in its side" .)