Entire opening from chess champion's letter? (5)
I believe the answer is:
total
'entire' is the definition.
(I know that entire can be written as total)
'opening from chess champion's letter?' is the wordplay.
I cannot really see how this works, but
'from' could be 'o' (I've seen this in other clues) and 'o' is located in the answer.
'letter?' could be 't' and 't' is found in the answer.
'chess champion' could be 'tal' (Mikhail Tal, 1936-1992) and 'tal' is present in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for total that I've seen before include "It might be grand" , "Everything added together" , "Including all" , "final answer" , "Count" .)