Friday

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The sixth day of the week.

from The Century Dictionary.

• noun The sixth day of the week.
• noun Any Friday marked by a great calamity: with special reference in England to Friday, December 6th, 1745, the day on which news reached London that the young pretender Charles Edward had reached Derby; or to the commercial panic caused by the failure of the house of Overend and Gurney, May 11th, 1866; and in the United States to the sudden financial panic and ruin caused by reckless speculation in gold on the exchange in the city of New York on Friday, September 24th, 1869 ; or to another similar panic there, which began September 18th, 1873.
• noun Among the Nestorians, the Friday after Whit-Sunday.

from the GNU version of the Collaborative International Dictionary of English.

• noun The sixth day of the week, following Thursday and preceding Saturday.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The sixth day of the week in many religious traditions, and the fifth day of the week in systems using the ISO 8601 norm; the Biblical sixth day of a week, the day before the Sabbath, or "day of preparation" in preparation for the Sabbath; the Islamic sabbath; it follows Thursday and precedes Saturday.
• adverb on Friday

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the sixth day of the week; the fifth working day