Two monkeys together? Learn one successfully seeks mates (11)
I believe the answer is:
grandmaster
'two monkeys together? learn' is the definition.
I can't tell whether this definition defines the answer.
'one successfully seeks mates' is the wordplay.
I cannot really understand how this works, but
'one' could be 'an' (an apple is one apple) and 'an' is found within the answer.
an anagram of 'mates' is 'maste' which is within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for grandmaster that I've seen before include "Expert on board" , "Senior chess player - senior mason" , "expert at playing pieces" , "Star chess player" , "a wizard with his pieces?" .)