Pervascope 

A type of telescope. It's basically one half of a pair of binoculars, designed to be used like a telescope for the same purpose.
Generally used by parents watching their kids play in a park from a long distance. However, it could be used for spying on people discretely, maybe checking out girls from a distance.

Two guys walking down a beach:
Guy 1: Yo, you see those chicks over there? You think we should go up to them?
Guy 2: I don't know, let me investigate further with my trusty pervascope!
(He takes a look down range.)
Guy 1: Well?
Guy 2: She has some nice titties...

Pervascope by /_7 December 17, 2008

Rusty Periscope 

The act of sitting on a girls face, with your balls resting on her eyes as if shes peering through the lens of a periscope, while she simultaneously jerks you off.

Jen is on her period this week, so I hopped on for a Rusty Periscope.

Rusty Periscope by Johnny Chimpo221 March 14, 2011

periscope fart 

When you press your butt against a hard, flat-surfaced chair and fart, but there is no place for the gas to escape except up the crack of your ass. and out at the top.

Dude, I laid the biggest periscope fart in detention. I press my butt cheeks against the hard chair and farted and the gas came bubbling up the crack of my ass and peeked out at the top!

periscope fart by Stagmen June 20, 2017

chocolate periscope 

When you take a giant dump and it's so big that the log sticks up out of the water like a chocolate periscope.

Dude come here I wanna show you my chocolate periscope!

What? Nooo Dude I'm not into men!

No you dork its in the toilet, check it out...

Duuuude that's awesome!!

chocolate periscope by minuccp February 20, 2011

Up periscope 

The act of hiding a random, uncontrollable boner by directing it upwards and binding it against your waist with your belt or pants waistband.

I had a boner that would just NOT GO DOWN, so I up periscoped it.

Up periscope by Sporklord February 19, 2011

the periscope 

The act of hiding your boner between your underwear and your belly so that it faces up 180 degrees, maintaining stealth. The head of the penis sticks out of the pants but is masked by the underwear, jeans, shorts, and/or shirt emulating a periscope. Using the periscope allows you to do everyday activities, while walking around with a massive errection. (for best results use with belt)

I felt nervous to solve the math equation in front of the class, but then I just used the periscope.

I hope parents don't get the wrong idea when I am at the daycare with my raging hard-on, thank God my step-dad taught me the periscope.

the periscope by John Paul VII August 26, 2012

Swedish Periscope

A sex act in which a woman (or man), in a crouching position, places their eye upon the anus of a standing male partner. They then proceed to grasp the shaft of the "periscope". Advanced users can then proceed to adjust the knobs of the periscope. The move is finished with a successful load blown, and a cry from the gazer of "fire the torpedos" as the recipient lets loose a fart. The fart should be moist so the gazer receives a maritime spraying of ocean wind.

Jim: Hey, uh betty. Ever looked through a swedish periscope?
Betty: Nope whats that?
Jim: come back home with me and ill show ya

Swedish Periscope by Dwarvish Lords of Miltonia September 29, 2008