Reciprocating Motion 

Movement characterized by repeatable back-and-forth motion.

"Jacob had some reciprocating motion in the bedroom."

Reciprocating Motion by Bass Genesis January 3, 2012

Non-Reciprocating Tool 

a completely self-absorbed, unaware "friend" (READ: douche) that you do things for *all the time* that NEVER returns the favor, even in times of crisis, always making the excuse that they're working or busy or just *can't* for whatever reason--always an excuse--ANY time you ask them, no matter what; someone who never returns the many favors you've done for them.

"My Dad just died and I can't find sittage for the funeral tomorrow. Since I've watched your kids for free for the past two days, do you think you can sit mine for a few hours while I go to my Dad's memorial service?"

Non-Reciprocating Tool: "Tomorrow? Oh, no way. Sorry. Gotta work online and stuff. You know. Busy and all. Can't. Maybe next time."

Non-Reciprocating Tool by Holly M S July 21, 2010

jebular reciprocation 

when you move your ahnd up and dwon the penis

also know as masturbating or wanking or pulling the plonker or burping the worm

jebular reciprocation causes bad eyesight

jebular reciprocation by lanky007007 May 29, 2007

Reciprocaling 

The act of taking one, then dividing it by another number to find the reciprocal of the number.

Not the real term; commonly heard in Middle or High school math classes.

Jeff: Okay, so I think I should be reciprocaling this number.
Jim: You mean finding the reciprocal of the number.
Jeff: Sure

Reciprocaling by That_Annoying_Sniper February 12, 2021

Like Reciprocation 

Like reciprocation is when somebody "Like"'s something on a website such as Facebook, and the person who received that "Like" reciprocates the like.

Somebody "Like"'d my status update, so I will find something to "Like" on their page, thus Like Reciprocation.

Like Reciprocation by Dr. Roswell August 20, 2014

Premature reciprocation 

Sending an additional email to someone after you already replied

"Thank you for replying (several times) to my email concerning the position we have on our relay race team. I assume suffering from premature reciprocation is difficult and somewhat embarrassing for you, but I encourage you to seek help. At this time I feel you would not be a good fit."

Premature reciprocation by NotWright January 1, 2021