Twitchel is a very old word for a narrow passage between walls or hedges (Old and Middle English- see OED). It is interesting to see that it and some of the other words mentioned here survive locally. Twitten is old Sussex, as noted by Vectis. Twitting is another word for the same thing. Not all words mentioned here are considered dialect, by the way, they are just seldom or locally used now. Long may they survive! Television and computer English are removing much of the flavor of the English language.