Assist fluid when there's no flow (6)
I believe the answer is:
stasis
'no flow' is the definition.
The answer and definition can be both states of affairs as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'assist fluid' is the wordplay.
'fluid' indicates anagramming the letters.
'assist' with letters rearranged gives 'STASIS'.
'when there's' acts as a link.
Can you help me to learn more?
(Other definitions for stasis that I've seen before include "Inactivity or stoppage of circulation" , "Stoppage of blood flow in body" , "Stoppage, arrest" , "Enduring state" , "Inactive state" .)