Method for passing through universe is not constant (7)
I believe the answer is:
osmosis
'method for passing' is the definition.
I can't tell whether this definition defines the answer.
'universe is not constant' is the wordplay.
'universe' becomes 'cosmos' (synonyms).
'not' suggests deleting specific letters.
'constant' becomes 'c' (common symbol in maths for an unknown constant).
'cosmos'+'is'='cosmosis'
'cosmosis' with 'c' taken out is 'OSMOSIS'.
'through' is the link.
Can you help me to learn more?
(Other definitions for osmosis that I've seen before include "Diffusion; assimilation" , "Miss Soo? (anag)" , "Absorptive process" , "Process of gradual absorption" , "Process of unconscious assimilation" .)