Definition:

a scientific expert and especially one involved in technological research

Example:

"Brain boffins at University College London have made a major breakthrough in the ongoing effort to bridge the gap between man and machine." – Rik Myslewski, The Register, April 11, 2011

About the word:

Boffin dates to 1945. Although its origin remains a mystery, it may have originated as a slang term for scientists engaged in wartime efforts.