Pressure too much, in case (3)
I believe the answer is:
pod
'case' is the definition.
(pod is a kind of case)
'pressure too much' is the wordplay.
'pressure' becomes 'p' (abbreviation).
'too much' becomes 'od' (abbreviation for overdose).
'p'+'od'='POD'
'in' is the link.
(Other definitions for pod that I've seen before include "Natural container for pea" , "A pea grows in it" , "A long seed-vessel" , "Seed case; whale herd" , "Seed case of peas" .)