Words

I was just reading The Influence of Discharge Chamber Structure Upon the Initiating Mechanism of the High Frequency Discharge by Sherwood Githens Jr., a Physical Review letter from 1940, when I came upon the delightful word preponderant, apparently a synonym for predominant. I think it is the first time I ever read that word, which is decidedly under used. However, a quick Google search furnished me with over 1.2 million hits for "preponderant", meaning that I have just been ignorant.

Many more obscure words can be found here