They might be shed by tense organs (5)
I believe the answer is:
tears
'they might be shed' is the definition.
(tears can be shed)
'by tense organs' is the wordplay.
'by' says to put letters next to each other.
'tense' becomes 't' (abbreviation used in many dictionaries).
'organs' becomes 'ears' (ear is a kind of organ**).
't' put next to 'ears' is 'TEARS'.
(Other definitions for tears that I've seen before include "Rents" , "signs of emotion" , "Rends" , "Water in eyes" , "Show of emotion" .)