Force measured in pascals (8)
I believe the answer is:
pressure
'force measured in pascals' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for pressure that I've seen before include "Type of organised group which tries to influence politicians" , "tension" , "Coercion, intimidation" , "Force measured in pascals" , "Force applied to a surface" .)