The term “twenty past four,” has different meaning in different professions. It has also been used to express different things in different parts of the world.
“twenty past four,” is a clock term. 20 past 4 is the clock time meaning the clock arm points 20 minutes past 4 O’clock. 4:20am or 4:20pm. The minute arm points 20 and the hour arm points 4, hence 20 past 4.
Like in the United States, the number represents a date, particularly in the 20th of April of every year. This day is acknowledged as a day of Marijuana Celebration together with the culture that is paired with it.
The expression is also used in food and beverage industry. It is used by waiters to remind them where to position the fork and knife. Waiters position fork and knive of 20 past 4 of the clock when serving a customer. They put the knife at position 20 of the clock minute arm and the fork pointing 4 of the clock.
There are other unclear expressions about 20 past 4 for example in the military and in the European football world.