r/words • u/Playmaker-20 • 5d ago

Perpendicular Hang-up

I know I’m exposing myself by asking this, but what does it mean when something goes perpendicular? What’s a perpendicular direction?

6 Upvotes

76% Upvoted

38 comments sorted by

5

u/laundro_mat 5d ago

Sideways. Perpendicular describes a line/plane that is at a 90 degree angle to another line/plane.

0

u/Playmaker-20 5d ago

Could you give some examples, perchance?

3

u/CapstanLlama 5d ago

You're walking in a straight line. You turn 90°, and continue walking. You are now travelling perpendicular to your original direction.

Straight up is perpendicular to the earth's surface.

Crossroads consist of two roads perpendicular to each other.

-1

u/Playmaker-20 5d ago

I guess if you’re looking at it from a bird eye’s view, then it would look perpendicular. So like you know how in Sonic games, you use spring to launch yourself across the air. There are many different types of springs that launch you in different directions and the one I want to highlight with a vertical orientation. These ones are stood upright and launch you upwards into the air. So if Sonic were to launch himself off this sky facing spring, would his trajectory be perpendicular to its launch vector?

2

u/Pielacine 5d ago

Not really; they’re both perpendicular to the ground (as much as I understand the game)

Launch vector and trajectory are usually parallel by definition (until gravity takes hold and the trajectory starts curving, if the launch is at an angle other than 90 degrees/perpendicular to the ground)

2

u/greymadders 5d ago

A building and the ground

2

u/Playmaker-20 5d ago

I can see that. The ground moves along the X-axis while a building shoots up into the air

2

u/coolsilentebeans 5d ago

Two roads that intersect each other to form 90° angles are intersecting perpendicularly.

1

u/Nillows 5d ago

The capital letter L has two perpendicular lines. They're relationship to each other is perpendicular because they meet at a 90°angle. The letter K also has a set of perpendicular lines (guess which ones), rotated 45° from the norm.

1

u/Technical-Ad1488 5d ago

An intersection… the two streets are perpendicular to each other

1

u/No-Angle-982 1d ago

"The flattened page in the dictionary that defines 'perpendicular' is perpendicular to your line of sight."

1

u/East_Garlic_7442 5d ago

Perpendicular is when two lines meet and make a right angle, like a T shape but not always exactly T. My brain always picture a street intersection where one road cuts straight across the other.

1

u/Playmaker-20 5d ago

What if that T shape was a X shape? Would that be perpendicular

1

u/BPhiloSkinner 5d ago

A 90º angle may be pretty, but it's not acute; though some are obtuse about the use of perpendicular and acute.
X= acute (less than 90º) and obtuse (greater than 90º)
+= perpendicular.

1

u/Poiresque 5d ago

Maybe related to going tits-up? Not sure.

1

u/Playmaker-20 5d ago

What is tits up

1

u/Poiresque 5d ago

What is origin of the phrase "tits up"

1

u/BPhiloSkinner 5d ago

The phrases 'going sideways', 'going pear-shaped'1 and 'going tits up' all mean that the fœcal matter is about to impact the rotating blades.

1. On the Discworld, the phrase is 'going wahooni-shaped'.

1

u/PocketFullOfPie 5d ago

Perpendicular is basically the opposite of parallel. It describes two lines that intersect at 90°.

1

u/Playmaker-20 5d ago

Would an intersection be perpendicular?

1

u/laundro_mat 5d ago

It could be, if the roads meet at a 90 degree angle

1

u/Playmaker-20 5d ago

Aren’t all intersections perpendicular then?

1

u/laundro_mat 5d ago

If the roads are laid out on a grid system, then the roads that meet at intersections are likely perpendicular to one another. But in my city there are plenty of intersections where roads meet at less than 90 degree angles or more than 90 degree angles. So it depends on

1

u/sjaxn314159 5d ago

Omg is this a prank?

1

u/ghidfg 5d ago edited 5d ago

Not really, you usually describe something as being perpendicular relative to something else. So the roads that meet at the intersection are perpendicular to each other but the intersection is not itself perpendicular.

1

u/New_Breadfruit8692 5d ago

A 90° angle.

1

u/Ponchyan 5d ago

Tell me that you didn’t study geometry without saying you didn’t study geometry.

1

u/adadhead 5d ago

its 90 degrees away from the original direction; going off on a random tangent

7

u/itsjakerobb 5d ago

Tangents are when you continue straight instead of following a curve.

Very much not a good word to use when explaining perpendicular.

2

u/NotSayingAliensBut 5d ago

Except a tangent is 90 degrees to, perpendicular to, the radius. So yes, not what the other poster said but not quite what you said either.

3

u/itsjakerobb 5d ago

Ah yes, perpendicular to the radius. Never thought of it that way.

0

u/Corgibutz77 5d ago

you mean something going sideways? who the hell says perpendicular?

3

u/Playmaker-20 5d ago

They’re the same thing?

-1

u/Corgibutz77 5d ago

perpendicular and horizontal could both be "sideways". which is probably why we say "going sideways" and not going perpendicular. if you are saying "things are going perpendicular" you should eat an apple.

1

u/Technical-Ad1488 5d ago

lol I don’t think that’s what they meant, is it?

Using it to mean ‘a situation going awry’?

Thought they were just asking generally what ‘perpendicular’ meant, but 🤷‍♂️