At any time; always (4)
I believe the answer is:
ever
I believe this is a double definition.
'at any time' is the first definition.
(synonyms)
'always' is the second definition.
(synonyms)
(Other definitions for ever that I've seen before include "Continuously" , "On any occasion" , "Always, at any time" , "In perpetuity" , "constantly" .)