Unfamiliar words, places, and sundry other references get added to the list with a view toward richer cultural and conversational engagement.

Recently Erased Ignorance
Ignorance Explained
1 prepossession a preconceived opinion; a prejudice
2 vitiate 1. To reduce the value or quality of; impair or spoil. 2. To corrupt morally; debase: synonym: corrupt.
3 recalcitrant having an obstinately uncooperative attitude; see also: CONGRESS
4 oast a kiln used for drying hops; like a chimney
5 lacuna an unfilled space; gap
6 integument natural covering in biology, such as skin, a husk, or shell
7 farrago hodgepodge, mishmash, etc.
8 homunculus a very small human or humanoid creature
9 wain a wheeled cart pulled by a horse and used for carrying goods or people
10 apposite apt in the circumstances or in relation to something

The full list can be viewed here.

Definitions appearing on this page are generally either verbatim or derived from Merriam-Webster's College Dictionary, Tenth Edition, 1999 or its online counterpart.