Xerox A trademark for a brand of photocopy machine. Never a verb. Use a generic term, such as photocopy.

X-ray (n., v. and adj.) Use for both the photographic process and the radiation particles themselves.

yam Botanically, yams and sweet potatoes are not related, although several varieties of moist-fleshed sweet potatoes are popularly called yams in some parts of the United States.

yard Equal to 3 feet.

The metric equivalent is approximately 0.91 meter.

To convert to meters, multiply by .91 (5 yards x .91 = 4.55 meters).

See foot; meter; and distances.

year-end (adj.)

yearlong

years Use figures, without commas: 1975. Use an s without an apostrophe to indicate spans of decades or centuries: the 1890s, the 1800s.

Years are the lone exception to the general rule in numerals that a figure is not used to start a sentence: 1976 was a very good year.

See A.D.; B.C.; centuries; historical periods and events; and months.

yellow journalism The use of cheaply sensational methods to attract or influence readers. The term comes from the "Yellow Kid," a comic strip, in the New York World in 1895.

yesterday Use only in direct quotations and in phrases that do not refer to a specific day: Yesterday we were young.

Use the day of the week in other cases.

yesteryear

Yom Kippur The Jewish Day of Atonement. Occurs in September or October.

Young Menís Christian Association YMCA is acceptable in all references.

Headquarters is in Chicago.

Young Womenís Christian Association YWCA is acceptable in all references.

Headquarters is in New York.

youth Applicable to boys and girls from age 13 until 18th birthday. Use man or woman for individuals 18 and older.

yo-yo Formerly a trademark, now a generic term.

Yukon A territorial section of Canada. Do not abbreviate. Use in datelines after the names of communities in the territory.

See Canada.

yule, yuletide

zero, zeros

zero-base budgeting A process that requires an agency, department or division to justify budget requests as if its programs were starting from scratch, or from a base of zero. In theory this assures a review of all programs at budget time.

zigzag

Zionism The effort of the Jews to regain and retain their biblical homeland. It is based on the promise of God in the Book of Genesis that Israel would forever belong to Abraham and his descendants as a nation.

The term is named for Mount Zion, the site of the ancient temple in Jerusalem. The Bible also frequently uses Zion in a general sense to denote the place where God is especially present with his people.

ZIP codes Use all-caps ZIP for Zoning Improvement Plan, but always lowercase the word code.

Run the five digits together without a comma, and do not put a comma between the state name and the ZIP code: New York, NY 10020.