“mergansers” are not waterfowl, they are the cold breezes your honey lets in the sheets when she rolls over.
Tampons are “Cramponis”
“Gouda, Sex and Becks” means “I don’t know, really” (“As good an explaination as any”)
Good moods have us singing “Ip zoo biddle ala boo”
Family phrases: “No spagetti, goodnight.” “No fair thinking!” and others that escape my mind…
The spouse and I use “Doot.” We’re both Dave Barry fans, and for some reason his references to “cat doots” made us both giggle, so now “doot” has become our all-purpose word. When one of us wants to know where the other one is in the house, we call, “Doot?” and the other one answers, “Doot!” It’s our default greeting on chat programs, meaning, “Are you there?” We sometimes call each other “doot,” as in, “Hey, doot!”
We also use it in its original sense to refer to what the cats leave in the litter box (the scoop is the “doot scoop” (as in that famous Beach Boys song “Little Doot Scoop,” of course! :D) and the bag they’re scooped into is the “doot bag,” (which is also our appellation, along with “doot-brain,” for stupid people)) but somehow we’re easily able to compartmentalize the two so we know we’re not calling each other cat-box products.
Hey, it works for us. 
Once upon a time, during a very long night of studying for finals, my friends and I created an entire hierarchy of men. All men fit into a category in our tree. It included “assholes,” “douchebags,” “geeks,” “nerds,” “dorks,” etc. Anyway, we coined a new word that night to describe a category heretofore without a name:
Rangstangler - this is the breed of men, almost invariable in their teens or twenties, usually stocky or heavy, who wear the button-up shirts with the flames at the bottom. They are usually a little sensitive and in madly unrequited love.
There’s also the Aberstangler, who dresses only in Abercrombie & Fitch. There is a personality that tends to go along with this too. Not that I judge people by their appearances or anything. 
We also started a tradition of extending the word “sure” into about eight syllables when it’s a single-word reply. For other single word replies, we always appended a normal “sure.” Examples: sure don’t, sure do, sure won’t, sure will, sure have, sure wanna, etc.
Back in the days of my mispent youth, when cruising around Isla Vista (the student ghetto next to UCSB), if a particularly hot young woman was spied nearby, one would acknowledge her allure with a double ring (“ling ling”) of one’s bicycle bell. This (maybe not so) subtle cue would cause all of us look around to see who was being so honored.
Hence a hot chick is still known as a “linger” amongst my circle of friends. I still expect this term to enter the popular lexicon. We actually had a bike bell mounted under the table at Sam’s To Go so that one could acknowledge hot chicks without getting up from one’s pitcher of beer.
Hmmm, it’s pretty hot out, I may have to go out to Isla Vista for lunch this week.
LIR - LOL in Real Life, for when we actually do laugh out loud
twatjack - semi-acronym for “that was just a chance to use the word…”. ie: I’m feeling labile today (twatjack labile)
hamas - means dumbass. Started when I said “ur a dumas” and my friend said “dumas is that party in palestine right?”
“Graminaceous.”
Of course, lots of people use this word – but the sense it developed in my peer-group over the past fifteen years is a bit more specialized:
“The Forbidden Zone is totally graminaceous.” (“If you’re considering watching The Forbidden Zone, you’ll want to smoke a joint first.”)
(Do the kids still call it “grass?”)
I picked up the habit (from a high school English teacher) of pronouncing that phrase English-phonetically rather than saying it in French (if you follow me) - something like “sest la vy”. The same teacher used to say “versi-vica” instead of “vice-versa” which confused me no end.
Grim
I distinctly recall it turning up in a TV jingle for a loan company in the '70s: “At Beneficial, you’re good for more…doot doot!”
Around my place, poopshnickel is a placeholder for anyone’s name we can’t remember. Whatsisface or so-and-so to you is poopshnickel to us. Derivation apparently from poopersnickle = a mischievous child (though the nameless individual need be neither mischievous nor a child).
My sister and I say, “let’s do Chuck!” instead of using the curse that rhymes with Chuck in certain situations.
The old song, The Name Game was our inspiration as kids.
A tough bowel movement is a “grumpy” (got it from a radio host)
One of my coworkers has this habit of roping people into really dull conversations. The remarkable thing about it is how predatory she is about it. One minute you might be walking along, then SNAP, you’re involved in a 10 minute one-sided monologue about her cats. Spectators regularly note how similar it is to a crocodile take down a small mammal. She’s that bad.
So, we’ve taken up using her first name to describe the act of trapping people in dull conversations, by pretty much anyone. “Bill can’t make it for another half hour–looks like he got Nancied* in the parking lot. Last I saw his mom was reading him the phone book.”
When I get home, I get all kissy faced with the dog - and I rub his tummy and coo at him - and I call him stuff like the Doglet of Love and stupid things like that. Husband usually doesn’t hear me (more likely he’s IGNORING me) but one day, he was yelling at Baron to get the hell out of the way and I yelled back at my husband, “Don’t yell - you’ll hurt his feelings! He’s the doglet of LOVE!” That stopped him dead in his tracks and he looked at me like I’d lost my mind. Now, everything he says has “let” after it. “Honeylet - want a beerlet of goodness?” “Bitchlet of cooking, where’s dinner?”
Stuff like that. This morning, it was “Snorelet of sleep, get the hell up - we overslept.” 
Yes, it’s getting old. Fast. Poor dog - he’s gonna need another name.
Fud. Pronounced like Elmer Fudd. Meaning food of any sort, but especially kitty chow. This is from my favorite Far Side cartoon EVER, the dog setting up his nemesis, the cat, to take a twirl in the household dryer by leaving a trail of cat kibbles leading to the appliance, with signs the dog himself has made that say “Cat Fud” with arrows. Meantime the dog is secreted behind a wall watching kitty nosh his way to the dryer, and he is saying, oh please, oh please! That cartoon hung on my fridge for YEARS, my sons and I laughed at it every time, and we began referring to everything edible as fud.
My dear departed mother used to say “Are you being have (pronounced HAYVE)?” instead of “behaving”, and I have now adopted that totally. Past tense is best: “When I get home, I better find that you were “hayve” while I was gone”, etc.
–Beck
We do this a little bit too–not for everything edible, but we do often refer to our cat’s food as “cat fud,” for the same reason.
We also use “kitty pudding” to refer to the meat baby food that we give them as a treat. I think they’ve learned the phrase, because they come running when I yell it.
A few years ago, I got into the habit of saying “go to slept.”
This has now become slepting (rare), needing to slept, etc.
Wow…I just keep remembering more of these, so if I’m annoying anybody, just tell me and I’ll shut up.
The spouse and I have our own silly names for various fast food restaurants, to the point where we pretty much never refer to them by their real names anymore. Chipotle is “Chipoodle,” KFC is “Kentucky Clucker,” Popeye’s is “Pope Yes” (the Pontiff of Poultry), Burger King is “Burner Thing,” and Quiznos is “We Love the Subs.” You can tell where we eat often by which fast-food joints rate silly names.
KFC to our family is “Colonel Buckets.”
My brother started to use the word “glop” as a verb, meaning “doing stuff/fiddling around.” Now my friends and their coworkers say “Oh, I’ve just been glopping around.”
My dad invented the word “motate,” which means to move and/or rotate, as in “get on the ball.” The aforementioned friends and coworkers now use this as well. “Let’s go–let’s get to motatin’!”
Weird, my family says exactly the same thing, but I’ve never heard it elsewhere. I googled, was given a corrected spelling of sufficiently suffonsified , and is of obscure origin.
A real phrase, just a rare one.
I don’t remember why, but my close friends and I refer to strawberries as strawbabies. I’ve always thought it was a little creepy sounding.
Amazing! I thought my Canadian husband had made this up. Thanks for the info!