Holders of equivalent positions facing anaesthetists (8,7)
I believe the answer is:
opposite numbers
'holders of equivalent positions' is the definition.
The answer and definition can be both related to thinking as well as being plural nouns.
Perhaps they are linked in a way I don't understand?
'facing anaesthetists' is the wordplay.
'facing' becomes 'opposite' (as in two things facing each other).
'anaesthetists' becomes 'numbers' (I can't justify this - if you can you should give a lot more credence to this answer).
'opposite'+'numbers'='OPPOSITE NUMBERS'
Can you help me to learn more?
(Other definitions for opposite numbers that I've seen before include "Workers who correspond" , "They may confront each other across the street" , "Rivals doing the same job" , "Counterparts" .)