Merriam-Webster's Word of the Day for August 14, 2008 is:

redoubt • \rih-DOUT\  • noun
1 a : a small usually temporary enclosed defensive workb : a defended position : protective barrier *2 : a secure retreat : stronghold

Example sentence:
From his redoubt on the ninth floor, the fugitive could see the line of police cars that had surrounded the building.

Did you know?
Based on its spelling, you might think that "redoubt" shares its origin with words such as "doubt" and "redoubtable," both of which derive from a Latin verb, "dubitare." But that's not the case. "Redoubt" actually derives via French and Italian from a different Latin verb -- "reducere," meaning "to lead back," the same root that gives us "reduce." How that "b" ended up in "redoubt" is a lingering question, but some etymologists have posited that the word might have been conflated with another "redoubt" -- a now-archaic transitive verb meaning "to regard with awe, dismay, or dread." Unlike its homographic twin, that "redoubt" does derive from the same root as "doubt" and "redoubtable."

*Indicates the sense illustrated in the example sentence.