Old key found in lift (5)
I believe the answer is:
exalt
'lift' is the definition.
(I know that exalt is a more specific form of lift)
'old key' is the wordplay.
'old' becomes 'ex' (prefix meaning former or onetime).
'key' becomes 'alt' (the Alt keyboard button).
'ex'+'alt'='EXALT'
'found in' acts as a link.
(Other definitions for exalt that I've seen before include "Raise high, glorify" , "Praise highly" , "Praise, glorify, or honour" , "Promote" , "Praise, glorify or honor" .)