In the early days of the Internet, the professor thought it might be easier for his students if he posted the definitions online. Plus, Rowlett, whose specialty field is geometry, wanted to try his hand at building a Web site.

He put his information in cyberspace, unaware of all the interest it would generate. Before long, others were linking to his Web site. Rowlett's e-mail box began to fill up with inquiries and entry recommendations from distant places.

"From around the world I would get these suggestions for different units," Rowlett said.

Often, someone would forward an ancient land measurement. Many such definitions survive generations of language changes because the words are used in deeds and legal documents handed down through the years.

A perusal of Rowlett's Web site reveals that a "marla" is a traditional unit of area in Pakistan, standardized while the British ruled the southern Asian country to be equal to the square rod, or 30.25 square yards.

A "kappland" is a land unit in Sweden that equals 184.5 square yards.

But Rowlett's site is not all about land measurements and volume.

There are hat size charts, grit sizes, the Glasgow coma scale, shotgun gauges, radiocarbon year conversion systems and more.

Most people are familiar with B.Y.O., or "bring your own," often at the bottom of party invitations. But would they know that "bya" is a common abbreviation in English-speaking countries for a "billion years ago?"

The derivation of "smoot," Rowlett says, is somewhat humorous.

In 1958, members of the Lambda Chi Alpha fraternity at the Massachusetts Institute of Technology measured the length of Harvard Bridge using pledge Oliver R. Smoot, all 67 inches of him, as the standard unit. The bridge, they say, turned out to be 364.4 smoots long -- plus an ear.

That bridge, which was resurfaced recently, is still marked in smoots. But, according to Rowlett's site, the "unit apparently got a little longer" when a taller relative of Oliver Smoot, a 1962 MIT graduate who became a lawyer, provided the new measurement.

"That one's a little different," Rowlett said.

Rowlett, a native of Virginia, started working at UNC-Chapel Hill in 1987. He came here after serving in the U.S. Army, then teaching at Princeton University for two years and then at the University of Tennessee in Knoxville for 13 years.

He teaches calculus, geometry and other math courses. Lately, he has devoted much of his time to the Center for Mathematics and Science Education, a School of Education program that provides resources for public school teachers and students across North Carolina. He also focuses on the recruitment of women and minorities into the field.

"One of the things I'm trying to work on with the School of Education is broaden the appeal of math," Rowlett said.

The son of a chemist and brother of an engineer, Rowlett thinks the fear that many people have of math dates back to a time when the subject matter was used to divide students into different educational tracks.

"Somehow mathematics became kind of a filter course in which students were separated and put into different groups, and that just scared them," Rowlett said.

With fun and useful projects like his Web site, Rowlett hopes to change that attitude.

But his efforts are not always ones that he broadcasts. Pat Bowers, who also works at the UNC-CH Mathematics and Science Center, found out by accident about the measurement Web site.

"He's a very unassuming person," Bowers said. "He just sort of does things, and you never know he's done them."

Rowlett also has Web sites devoted to lighthouses, his family history and tropical storms. His interests are varied, he says, but he's always looking for unusual measurements.