1a. a smug, ignorant, especially middle-class person who is regarded as being indifferent or antagonistic to artistic and cultural value. b. one who lacks knowledge in a specific area.

The first definition of this word is “a member of an Aegean people who settled ancient Philistia around the 12th century b.c.” But I like the other definitions better. Also, while these definitions are for the noun, philistine can also be used as an adjective. The American Heritage Dictionary has a nice summary of this word’s history.