Calm down about stress (8)
I believe the answer is:
restrain
'calm down' is the definition.
The definition and answer can be both to do with human feelings as well as being verbs in their base form.
Maybe they are linked in a way I don't understand?
'about stress' is the wordplay.
'about' becomes 're' ('re' means regarding or about).
'stress' becomes 'strain' (synonyms).
're'+'strain'='RESTRAIN'
Can you help me to learn more?
(Other definitions for restrain that I've seen before include "bottle up" , "Stop" , "use handcuffs?" , "Keep back" , "bar" .)