Confessions of Ignorance is another gem of a blog. Its author, Seana Graham, took to heart what your English professors constantly harped on--if you don't know what a word means when you encounter it, look it up.
Seana is a bookseller in Santa Cruz, California and quite the prolific blogger. Not only does she manage four of her own blogs, but she is a frequent contributor to other blogs.
Some of her recent vocabularic explorations are: shibboleth, infamy, scintilla, paean, and synecdoche. Confessions always makes for interesting reading, because often when I think I know a word, I find out I don't quite have it. It's a shock to the literary system when you take the time to look up a familiar word and realize that you haven't always used it correctly.
Also, Seana's blog has reinforced the cold, hard truth that deriving meaning by "context" doesn't work all the time. It's no substitute for cracking the Webster's.
3 days ago