15
LSD or acid (lysergic acid diethylamide) is the most commonly used hallucinogen (also known as psychedlics). It is considered a typical hallucinogen causing similar effects to other hallucinogens like mescaline, psilocybin (mushrooms), and ibogaine. LSD became popular in the counterculture of the 1960s and 1970s, but since then its use has been limited to people in the Rave or club scenes. According to the College Alcohol study, only 9.4% of Brown students have ever used LSD.

LSD is usually taken by ingesting small tabs of paper (frequently placed under the tongue) which have been soaked in the liquid form of the drug then dried. In rare cases it is taken in a liquid, gelatin, or tablet form. Sometimes a dose is soaked into a sugarcube. Doses range from 20 to 100 micrograms now, though in the 1960s they ranged from 100 to 200 micrograms. Because LSD is produced illegally, it is difficult to know how strong a dose is. The effects of the drug begin in about 30 minutes and last up to 12 hours. It can be very difficult to sleep if LSD has been taken in the last 6 hours.
acid is a very powerful drug,
but it is not as damaging as many people like to portray it.
by tjbcreations February 07, 2008
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16
In computer science, ACID (Atomicity, Consistency, Isolation, Durability) is a set of properties of database transactions. In the context of databases, a sequence of database operations that satisfies the ACID properties and, thus, can be perceived as single logical operation on the data is called a transaction.

It's also slang for LSD, apparently.
That database is not ACID, but this may not be a bad thing, if you understand the trade-offs.
by DefinrOfWords February 13, 2017
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17
A style of techno/house music, noted for its prominent use of the of the Roland TB-303, a synthesizer with a distinctive (and very funky) sound. Variants include hard acid, acid house, acid trance, etc. Not all music that includes a 303 is necessarily acid, and not all acid music makes use of the 303 (but most of it does).

Some suggest that the word is derived from the phrase "acid burn" - a slang term from the early days of house music, referring to the practice of sampling from another musician's records (see bite).

Others cite a 1985 house single by Phuture called "Acid Trax", which is recognized as one of the first house records to make use of the 303.

A more concrete theory is that it refers to the drug LSD, which is commonly used at raves where acid house is played. Given the psychedelic nature of acid house, this interpretation is certainly part of the popular understanding of the term, if not necessarily its historic origins.
Drum & bass is okay, but what I really want to hear is some nice tweaky acid.
by Greenie December 10, 2003
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18
LSD was first synthesized in 1938 by Swiss chemist Dr. Albert Hofmann at the Sandoz Laboratories in Basel, Switzerland, as part of a large research program searching for medically useful ergot alkaloid derivatives. Its psychedelic properties were unknown until 5 years later, when Hofmann, acting on what he has called a "peculiar presentiment," returned to work on the chemical. He attributed the discovery of the compound's psychoactive effects to the accidental absorption of a tiny amount through his skin on April 16, which led to him testing a larger amount on himself for psychoactivity.

sadly the acid that is taken today compaired to 20 years ago is a basterdised version with more effects to physical sensation and a reduction in auditory and visual stimulation. it is said to be a hallucinogen but in it has been proven scientificaly that it actualy causes a temporay break down in a mental berior wich causes you to notice signals that you would normaly not notice it also sticks a door stop in the door to your subconcious wich allows your emagination to run wild there by the hullucination is based on an actual event taking place.
guy1 "dude i took a bad hit of acid last night and i had no clue what was going on."

guy2 "you meen you took real acid last night not that stupid wuss bag shit u normaly took and had the best trip of your life u fuckin tard."
by luke neville November 17, 2006
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19
A substance which has a high concentration of positively-charged hydrogen ions.
Vinegar is a weak acid.
by Polychromophilia December 09, 2004
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20
1. adj. A way of being which is negative and/or hurtful.
Jenny: Your shoes suck, Jimmy!
Jimmy: Yo Jenny, why you gotta be so acid?
by JohnnyHotcakes99 May 27, 2016
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21
a drug which jesus gave away for free, the church wanted a monopoly on the drugs so they killed him.
acid is good to take before lectures.
I had to put my friend in hospital on a bad trip.
by james kirk March 16, 2006
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