THE ABCs OF 'CSI'

-- AFIS (automated fingerprint identification systems) A database used to scan and store fingerprints.

-- ALLIGATORING A blistering pattern on wood burned at extremely high temperatures that resembles the skin of an alligator.

-- ALS (alternate light source) High-intensity light that can enhance or discover the presence of fluids, fibers, fingerprints, and trace materials.

-- ''CALL SOMEONE WHO CARES'' The humiliating message sent by a hitman who inserted a quarter in his victim's head wound.

-- CODIS Short for Combined DNA Index System, the FBI-operated database of genetic samples.

-- DENTAL SOCIETY Organization that oversees the nation's dental-print databases.

-- DISCO PLACID A Vegas-area jazz producer who hears in perfect pitch. Grissom consults him in order to analyze a sound recording.

-- ELECTROTHERMAL ATOMIZER A device Willows used to detect art forgery by identifying modern-day substances in paints.

-- EQUIVOCAL EVIDENCE Guideline quoted by Capt. Brass thusly: ''When faced with evidence that could equally exonerate or implicate a suspect, we must, as objective interpreters of that evidence, side with the defendant.''

-- FIRST WITNESS, FIRST SUSPECT A self-explanatory investigative rule of thumb.

-- FORENS-L An e-mail discussion group frequented by forensics professionals.

-- GLASS FLOTATION A method of determining the density of a piece of glass by immersing it in various liquids.

-- GRIBBS, HOLLY New recruit to Grissom's staff who dies -- in episode 2! Her case is investigated by Sara Sidle.

-- HAECKEL MARKS Fracture marks on broken glass which indicate whether it was broken from the inside or the outside.

-- HEMORRHAGIC TISSUE The presence of this blood-nourished tissue on bone indicates that a dismemberment victim was alive at the time of the injury.

-- ION DETECTOR Used by Brown to determine the presence of fire accelerants in the air.

-- LINEAR REGRESSION Process in which Grissom calculates the time of death by determining the age of insects on a corpse and figuring backward.

-- MARLOWE, MELISSA The kidnap victim who resurfaces 21 years later, under a new identity, and murders her ''father.'' She runs away after Willows sees through her insanity plea.

-- MALANDER, PAUL The eccentric proprietor of a costume store that manufactured prosthetic hands (one of which featured Grissom's fingerprints) which he used to get away with murder.

-- MO Law-enforcement slang for moron.

-- PAGER NEST A device that identifies numbers called to a pager.

-- PETECHIAL HEMORRHAGES Pinpoint red dots in the eyes of a victim indicating strangulation.

-- PHENOLPHTHALEIN A chemical that, when combined with hydrogen peroxide, will reveal the presence of blood by reacting with its hemoglobin and turning a cotton swab pink. (Also known as the Kastle-Meyer color test.)

-- PRECIPITIN TEST An antibody test used to determine whether a bloodstain is human.