You and I take time for an application (5)
'an application' is the definition.
(I've seen this before)
'you and i take time' is the wordplay.
'you and i' becomes 'us'.
'take' means one lot of letters go next to another.
'time' becomes 'age' (an age is a period of time).
'for' is the link.
(Other definitions for usage that I've seen before include "Usual practice", "Interest of old", "Accepted or habitual practice", "Customary way in which language is spoken or written", "Style of language".)