Skip to main content

Bicycle Day 

Bicycle Day is April 19, commemorating April 19, 1943, when Dr. Albert Hofmann first took LSD intentionally. Three days earlier, he had absorbed a small amount of the drug either through his fingertips or by accidentally ingesting it. On Bicycle Day, he took 250 µg of LSD intentionally and, fearing he had made himself ill, cycled home from his lab. During his bicycle ride, he experienced the effects of LSD, making this the date of the first ever acid trip. He wrote about his experiments and experience on April 22, which was later put into his book LSD: My Problem Child.
This day (for LSD users) is when they celebrate the discovery and first ever use of the drug
acid LSD trip
joe spent bicycle day at home with 250 grams of LSD, just as the amazing albert hofmann had done in 1943
Bicycle Day by SpamWeed May 1, 2006
Urban Dictionary Merch
Your favorite words on things you can wear, drink from, read, or give to a friend.
The Urban Dictionary Store sells gifts you’ll have to explain.

Bicycle Day 

Bicycle Day is April 16, commemorating April 16, 1943, when Dr. Albert Hofmann first took LSD intentionally. Three days earlier, he had absorbed a small amount of the drug either through his fingertips or by accidentally ingesting it. On Bicycle Day, he took 250 µg of LSD intentionally and, fearing he had made himself ill, cycled home from his lab. During his bicycle ride, he experienced the effects of LSD, making this the date of the first ever acid trip. He wrote about his experiments and experience on April 22, which was later put into his book LSD: My Problem Child.

This day (for LSD users) is when they celebrate the discovery and first ever use of the drug.
Phoenix spent Bicycle Day at home with 250 grams of LSD, just as the ineffable Albert Hofmann had done in 1943.
More from Urban Dictionary

Slop Grenade

When someone uses AI to generate a large document, slide deck, or piece of code/software and tosses it over the fence for you to deal with.
Chad: Hey Brent I sent you the new backend API change to review, it’s only 100 files changed.

Brent: he just tossed me a slop grenade
Slop Grenade by Joe Squid September 28, 2026
Word of the Day on September 29, 2026
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).
After we broke up, he was floxi to me.
floxi by Dr. Geek May 13, 2009
Word of the Day on September 28, 2026
NYC people who migrate north to Quahog, RI to see the leaves in the fall.
New York and everyone from there can fornicate themselves with an iron stick.
leafers by ss++ February 8, 2005
Word of the Day on September 27, 2026

Respectfully 

Precedes or follows either a gratuitously disrespectful or honest remark, originated in New York City. Used in similar fashion to "no offense" or "to be honest," interchangeably.
Ya mans is wild buns, respectfully. Respectfully he's washed.

After school, The Modells on Jamaica Ave was active. Respectfully.
Respectfully by john quan the first December 20, 2020
Word of the Day on September 26, 2026

You met me at a very Chinese time in my life

A moment in time where you feel distinctly Chinese over all other things.
Dante: "I wish I could be Nigerian, but I can't because I'm Chinese. You met me at a very Chinese time in my life."
Word of the Day on September 25, 2026
Load more