What, if anything, is the difference between a wonk, a geek, a nerd and an anorak? | Notes and Queri

What, if anything, is the difference between a wonk, a geek, a nerd and an anorak?

Terry Norman, Ammanford, Wales

• In the US there are significant differences between these words. A "wonk" is an expert on a practical matter, especially in government, as in "policy wonk". A "nerd" is knowledgeable about arcane matters such as science and computers but has social skills. A "geek" is a nerd with no social skills. Bill Gates was a notorious geek, with unwashed hair and ugly clothes. Now he has an attractive wife and gives away money by the the carload. He's now a nerd. In the US, anorak is a rarely used word for a pullover parka. The word isn't used to identify trainspotters (called "railfans") and their like.

  David Null, Claremont, California, USA

• In the 1947 film "Nightmare Alley", the Geek is a kind of freakshow performer of uncertain nature: he acts the wildman, gibbers and jabbers like a crazy person, and lives in a cage like a gorilla. By the end of the film, the hero Stan (Tyrone Power), a drink-ruined wreck, will take any job in the circus - and is thus reduced to playing the Geek himself.

  John Bennett, Glasgow, Scotland, UK