Boffin

In fact, a fighting friend of mine said that he could hardly walk in any direction in this war without tumbling over a scientist who had got in the way. In the Royal Air Force, where the concentration of scientists is perhaps greatest, they have a pet name for them. They call them “Boffins.” Why, I do not know. I said to a young friend of mine in the Air Force, “Why do you call scientists ‘Boffins’?” He said, “I don’t know. What else would you call them?”

Source: wiktionary

With a rare and beautiful ease one can now ring up a boffin, as I did the other day, and say: "As a price for not opposing our Parliamentary Powers for a new marshalling yard, the Council at X demands that the bridge over X Lane shall have 16 ft. 6 in. headroom. This means steepening our gradient from 1 in 70 to 1 in 65 for half a mile on a 20-chain curve. What difference will this make to the loads of Type "2", "3" and "4" diesels please?". Back comes the answer.

Source: wiktionary

An essential difference between a boffin and a back room boy, as [Robert] Watson-Watts points out, is that the boffin does not stay in the back room but emerges to poke his nose into other peoples[’] business. It is quite wrong to use the word ‘boffin’ simply to describe a scientist or a technician; a boffin is essentially a middleman, a bridge between two worlds, […]

Source: wiktionary

He devoted six years to building the probe and, breaking with boffin tradition, transformed himself into an extroverted fundraiser to sell it to a public and government largely indifferent to space exploration. […] In fact, he's still busily rallying support for Beagle 2’s successor. Will he succeed? Can a lone boffin maintain a nation’s appreciation for exploration? [Colin] Pillinger could single-handedly determine whether the boffin remains a modest backroom boy or claims a lasting spot in the limelight.

Source: wiktionary