The system devised by the Annular Bearing Engineering Council to rate the precision of the bearings manufacture. The higher the ABEC number, the tighter the manufacturing tolerances are held. The ABEC number is always odd (1,3,5,7), but it has no relation to the quality of the materials that the bearing is manufactured from.

ABEC is a rating system used by the bearing manufacturers. Usually the higher the rating (ABEC 1 vs. ABEC 3 vs. 5 vs. 7) the more precise and smooth the ride is. The ABEC rating does not, however, determine the speed of the wheel, and is in no way a measure of the quality of the wheel.

ABEC 3 is an AMBA tolerance class. C3 is an internal clearance specification. Fit is the relationship between the bearing bore and outside diameters to the housing bore and shaft outside diameter. Tolerance, clearance and fit are independent dimensions, although in some cases choosing a larger internal clearance can allow you to use a tighter interference fit. Please contact NTN engineering for details.

Well apparently it has to do with something called gene expression, which refers to the pattern in which genes are switched on and off. And gene expression has a major effect on your body's biological processes. Each cell in your body contains a 'power-factory' that produces energy, called the mitochondria.

Isotonic solutions cause no swelling or contraction of the tissues with which they come in contact, and produce no discomfort when instilled in the eye, nasal tract, or other body tissues.

The tonicity of the solution is less than that of the cells. When this occurs, water enters into the blood cells causing them to swell and finally burst, with the liberation of hemoglobin, or water invasion of the body’s cells. If this invasion is beyond the body’s cells, then water intoxication results, with convulsions and edema.

The tonicity of the solution is greater than that of the cells, which can cause a variety of complications, such as, hyperglycemia, intracellular dehydration, loss of water and electrolytes, dehydration and coma.

Here a "hack" is a clever shortcut or a lesser-known, faster way to get something done. A hacker believes that information-sharing is a powerful positive good, and that it is a hacker's duty to share her expertise—so we will.

Please see RTFM in the Jargon File. Posters please note: Moderators are unlikely to approve follow-ups that consist solely of "RTFM".

Read The Fine FAQ, a variant of RTFM. Also RTFAQ Posters please note: Moderators are unlikely to approve follow-ups that consist solely of "RTFF".

If air at the brochure rate is unavailable, we will offer the next best alternate to you. You always have the option to revise your departure city or make the booking land-only, prior to ticketing, if the up-sell charge is unacceptable. Back to top

STD is short for "sexually transmitted disease." Another term you may have heard is "venereal disease," or VD.

The word hatha means willful or forceful. Hatha yoga refers to a set of physical exercises (known as asanas or postures), and sequences of asanas, designed to align your skin, muscles, and bones. The postures are also designed to open the many channels of the body?especially the main channel, the spine?so that energy can flow freely. Hatha is also translated as ha meaning "sun" and tha meaning "moon.

John Lennon and his friend Stuart Sutcliffe came up with the name "Beatles", a pun on Buddy Holly's "Crickets", in 1960.