hypermiling
"It is my absolute favorite time of the year on the OUPBlog. Word of the Year time (or WOTY as we call it in the office). Every year the New Oxford American Dictionary prepares for the holidays by making its biggest announcement of the year. The 2008 Word of the Year is (drum-roll please) hypermiling."
http://blog.oup.com/2008/11/hypermiling/