In a terrible rut, information is important (6)
I believe the answer is:
urgent
'important' is the definition.
(I've seen this before)
'in a terrible rut information' is the wordplay.
'in' indicates putting letters inside.
'a terrible' indicates anagramming the letters.
'information' becomes 'gen' (gen can informally mean information).
'rut' anagrammed gives 'urt'.
'urt' going around 'gen' is 'URGENT'.
'is' is the link.
(Other definitions for urgent that I've seen before include "demanding speedy action" , "In need of immediate action" , "High priority" , "Demanding immediate attention" , "Important and in a hurry" .)