An experiment at Rugby? (3)
I believe the answer is:
try
'an experiment' is the definition.
(I've seen this in another clue)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for try that I've seen before include "Endeavour" , "Make an effort to get rugby score" , "Make an attempt" , "Test; attempt" , "Attempt; smooth (wood)" .)