Chuck Berry at last embraces Alfa Romeo's digital system (6)
I believe the answer is:
binary
'digital system' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'chuck berry at last embraces alfa romeo's' is the wordplay.
'chuck' becomes 'bin' ('bin' can be used as a verb).
'at last' says to take the final letters.
'embraces' means one lot of letters goes inside another.
'alfa romeo' becomes 'ar' (this could be a standard abbreviation which I don't know about).
The final letter of 'berry' is 'y'.
'bin'+'y'='biny'
'biny' placed around 'ar' is 'BINARY'.
Can you help me to learn more?
(Other definitions for binary that I've seen before include "Arithmetic system to the base of 2 as used by computers" , "Using the digits 0 and 1" , "A system of two stars" , "Of a system using 2 rather than 10 as its base" , "Involving two things" .)