Initially, let elderly aunt stay, effectively guaranteeing tenure for a while (5)
I believe the answer is:
lease
'guaranteeing tenure for a while' is the definition.
I can't tell whether this definition defines the answer.
'initially let elderly aunt stay effectively' is the wordplay.
'initially' says to take the initial letters.
The first letters of 'let elderly aunt stay effectively' is 'LEASE'.
Can you help me to learn more?
(Other definitions for lease that I've seen before include "Contract to rent" , "From legal document" , "Let out, hire" , "Rent -- easel (anag)" , "Property rental agreement" .)