after one has acquired an erection and is desperate to make it unnoticeable, or gone, they put there penis in the Vietnamese chokehold, this is where you take your penis and position it so that is is pointing towards your belly button make it so that the girth of it is firmly restrained by the belt line, making it unnoticeable. the act of doing this can also cut off circulation, difusing the blood quickly. getting rid of the erection quickly and easily.
adam:so the other day in gym class i popped one, do you know what i did
Doug: What could you have done adam? everyone hates gym class randoms.
Adam: well i pulled a Vietnamese chokehold, cured it right up.
Doug: Cool story bro, tell it again sometime!