Feeling of tension in body, not in ears (4)
I believe the answer is:
knot
'feeling of tension in body' is the definition.
'knot' can be an answer for 'body' (thesaurus). I am unsure of the 'feeling of tension in' bit.
'not in ears' is the wordplay.
'not' becomes 'no' (negative).
'in' means one lot of letters goes inside another.
'ears' becomes 'kt' (I can't justify this - if you can you should believe this answer much more).
'no' placed within 'kt' is 'KNOT'.
Can you help me to learn more?
(Other definitions for knot that I've seen before include "Ring < sandpiper" , "To secure < > bird" , "Unit of speed used by ships" , "Fastening such as reef or granny" , "Assemblage" .)