It was used exclamatorily, e.g., to get publicity (4)
I believe the answer is:
egad
'it was used exclamatorily' is the definition.
The definition suggests a singular noun but the answer is not.
'e g to get publicity' is the wordplay.
'to get' means one lot of letters go next to another.
'publicity' becomes 'ad' (short for advert).
'e'+'g'+'ad'='EGAD'
Can you help me to learn more?
(Other definitions for egad that I've seen before include "Mild oath (archaic)" , "Mild oath - aged (anag)" , "Old exclamation; aged (anagram)" , "Forgotten curse" , "Archaic exclamation of surprise" .)