A Dead Mom Kid is a person who takes what was intended to be a lighthearted, funny, stupid, and/or silly joke or moment and suddenly makes it awkward and serious by bringing up really personal details about themselves that you would figure to be something they want to keep in their private lives. Often times they do this very casually or try to talk about it like it's funny and you suddenly don't know what to say to them other than "that sucks" or "wow I'm sorry" to be polite. Often accompanied with trying to disengage oneself from the situation by means of excuse accompanied with a silent vow to never speak to said person again.
This most commonly happens when someone makes a casual "your mom" joke and the receiver of the joke responds with something along the lines of "My mom is dead" whether the joke was meant to be offensive or not.
A jovial term used in reference to a friend or co-worker whom is having or has had a retirement party at work. The party must have refreshments/snacks for the term to apply.
This term comes from the behavior seen when a bug dies on a sidewalk or other observable location. Other bugs will notice the dead bug and stop by to tear a chunk off to eat. Similarly, a co-worker is retiring (dying in a sense) and the other co-workers stop by to grab a snack/drink ( much like tearing off a chunk to eat). Thus the retiree is the 'dead bug'.
Origin of this term is from an IBM site in Rochester, MN.
Hey, we got a deadbug in the break room!
Great, I could go for a doughnut.