Greek letter from English essayist to American lawman (6)
I believe the answer is:
lambda
'greek letter' is the definition.
(letter from the Greek alphabet)
'english essayist to american lawman' is the wordplay.
'english essayist' becomes 'lamb' (I've seen this before).
'to' means one lot of letters go next to another.
'american lawman' becomes 'da' (I am not sure about the 'american' bit.).
'lamb'+'da'='LAMBDA'
'from' acts as a link.
Can you help me to learn more?
(Other definitions for lambda that I've seen before include "Teasing entertainer" , "Greek letter - am bald (anag)" , "Not one of our characters" , "The 11th letter of the Greek alphabet" , "Foreign character" .)