For each or every (3)
I believe the answer is:
per
I believe this clue is a double definition.
'for each' is the first definition.
(per person)
'every' is the second definition.
('per' means 'for each' or 'for every')
(Other definitions for per that I've seen before include "According to" , "Preposition meaning for each" , "Preposition indicating by means of" , "For each or every" .)