1) Adolf Hitlers Day of birth.

2) Smoking Holiday (4/20 any year)

3) Rumored Some college students would smoke everyday at 4:20 pm
My PC clock says 4:20 haha.
by BObo D. HObo July 22, 2004
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Possibly the best/worst day to have a birthday, in college. Since everyone will be stoned, you'll probably have a 100% of people forgetting it's your birthday, but also an equal chance of getting lit up for free when you remind them.
Birthday dude: hey you know what day it is?!?
Friend: 4/20!!!!!! Time to get baked!
Birthday dude: No asshole... it's my birthday.
*The friend surrenders his bong to the dude with the birthday*
by Chillbro April 20, 2017
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national weed smoking day. light em up at 4:20 pm or am.
man, i cant wait for 4-20 to come. its almost as good as christmas.
by ... April 24, 2005
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The "official time" to smoke it up...
The original story:
A small group of kids in high school used to meet up everyday after school at 4:20 and smoke on the hill. One day on April 20th, at 4:20 they were all like "woa...it's 4:20, and 4/20- we should make this celebration official" the celebration spread and now 4/20 is an amazing day to get blazed thanks to a group of high school kids from norcal from the 70's
dude...it's 4/20...let's get blazed
by marinite June 17, 2005
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The day in Colorado when at literally any location in the state, you can just take a big whiff and smell weed.
by cinimodde April 20, 2019
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One of the many names for weed. Its mainly in reference to time. But theres also April 20th.
Its 4:20, gota hit that bowl.
I cant wait til 4/20,(april 20th) Im gona be stoned off my ass.
by Sonja February 19, 2003
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1. Natioinal Smoke Marijuana Day.
2. Hitler's Birthday.
1. Stoner 1: Hey man it's 4/20! We finna get high as hell!
Stoner 2: Fasho!

2. Happy Birthday Hitler?
by cubear69 April 27, 2009
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