An oral test (7)
I believe the answer is:
tasting
'an oral test' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
This is the entire clue.
Can you help me to learn more?
(Other definitions for tasting that I've seen before include "Savouring" , "Sampling (food)" , "event with wine" .)