Wagshal Shift - a popular plate variety on the five cent 1847 stamp, discovered by collector Jerome Wagshal

War Emergency Rate - a tax, in the form of increased postage rates, to help pay for World War I. The rate for letters was increased from two cents to three cents per ounce, and the rates for postcards from one cent to two cents. The war emergency rate remained in effect from November 2, 1917 until July 1, 1919, when the pre-war rates were restored.

War Savings Stamps - stamps issued by the Treasury Department during both World Wars, redeemable for War Certificates in WWI and for Defense Bonds or War Bonds during WWII.

Washed - a used stamp that has had its cancel removed, sometimes chemically, either for illegal reuse or to deceive collectors

Washington Bicentennials - a set of commemorative stamps issued in 1932 to celebrate the bicentennial of Washington's birth

Washington-Franklin Head Issue (Series of 1908) - The Third Bureau Issue, the Washington Franklin Series has more varieties than any other U.S. issue.
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Waterbury Cancels - fancy, often pictorial, cancels used in Waterbury, Connecticut from 1865-1870. They were the artistic creation of its postmaster.

Watermark - a design, letter or letters embedded in paper during the paper manufacturing process, often used in securities to distinguish counterfeits
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Way Letter and Markings - a letter collected and postmarked by an official mail carrier on his way between two post offices

Web - a continuous roll of printing paper used for printing rotary press stamps

Web-fed - the process of printing from a roll (web) of continuous paper, as opposed to the process of printing on individual sheets of paper fed one sheet at a time

Wells Fargo and Company - a company that issued stamps and applied cancels to envelopes

Wet Printing - engraved printing on paper that has been moistened to render it soft and pliant in order that the paper will press into the engraved lines of the plate under less pressure, thus facilitating the transfer of ink.

White Plains Sheet - the first souvenir sheet (SS) issued by the U.S., honoring the Battle of White Plains. The White Plains stamp was a normally issued commemorative stamp of 1926.

White, R.H. - noted color expert and author of "The Encyclopedia of the Colors of United States Postage Stamps"

Willard, Edward L. - the author of "The United States Two Cent Red Brown of 1883-1887"

Without Gum - an unused stamp issued with gum, that no longer has gum

Worn Plate/ Worn Impression - a plate where parts of the design of some of the stamps are so worn that they fail to print properly

Wove Paper - (as opposed to laid paper) The most commonly used paper in stamp production, wove is a smooth even-finished paper showing few differences in texture and thickness when held to light.

Wrapper - a sheet of postal stationary with an imprinted stamp-like design that can be folded around a newspaper or periodical and sealed for mailing