I was watching QI on television just now and Stephen Fry said Charles Dickens coined the word boredom.
Many sites on the internet agree that Dickens was the first to use this word in print, in his novel Bleak House, giving as the date 1852, but Language Log says the word was first used in print in 1864.
I hadn't realised that Dickens invented words, but of course it's obvious he would have, as all good writers try to find new ways to express their ideas. According to Words That Teem With Meaning; Copenhagen Views on Lexicography, Dickens did indeed invent (or use for the first time) lots of neologisms. Some, like gunpowderous, had a short life, but we still use allotment garden and casualty ward today.
A journal called Charles Dickens:Linguistic Innovator looks interesting and can be purchased online.
Update 6 June 2016. Thanks to a comment by Paul Vargas, I've learned that Dickens was not the first to use this word in print. I've made a new post to explain what he told me.