The idiom "red flag" is a metaphor referring to a warning of potential danger or of an impending larger problem.
The origin likely derives from literal red flags or banners used to issue warnings to observers.
The oldest documented use dates back to the 17th century when militaries of European origin or tradition used red flags to indicate imminent combat or potential for attack to opposing forces. These military red flags were used on land and at sea.
A red flag to indicate danger or a warning had moved from the military to common noncombatant usage by the 18th century, according to writing from the period.
Both military and non-military use likely dates back further, but can't be verified via surviving documentation.
In modern vernacular, the use of "red flag" very rarely refers to an actual piece of crimson fabric—except in sports like racing or football.
Today, red flag usually refers to problematic words or behavior from family, friends, significant others, or public figures.
Reddit user Radiant_Blooom asked:
"What is a red flag to see in someone's home?"
Excuse me?
"I was looking at an apartment to rent in a very liberal part of the USA. Place was great!"
"I’d have a huge windowed area and lots of nice amenities like a fireplace. I went to the other part of the place where the landlord lived."
"Above his fireplace was a portrait. A portrait of Nathan Bedford Forrest. Founder of the KKK."
"I noped right the f*ck out of there."
~ _CMDR_
Parched
"When their pets water bowls are empty."
"Monsters."
~ LoJellythings
"My wife doesn't abide this. Whenever we're at someone's house, she'll just pick up the water bowl, wash it, and refill it for the critters if needed."
~ tesseract4
Maybe They Have A Maid
"No cleaning supplies."
~ ZooperScooper77
Effortless
"When they don't do basic preparation for a preplanned guest coming over."
"For example, there's no toilet paper, they don't offer you anything to drink, house is really messy."
~ AriasK
Literal Flags
"Large political flags on the wall. I don't care what your political affiliations are, if you are that obsessed with it that you feel the need to hang a huge flag in your living room to announce them, that's a no from me."
~ NoFunction_
"Exceptions are made for those with giant flags for the United Federation of Planets. I can definitely hang with most nerds."
~ knitwise
"The flag of the Klingon Empire is a red flag, and I would like to see it in someone's home."
~ LBXZero
Shepard Fairey Fan
"There was a guy who posted on the subReddit r/malelivingspace who has 3 ‘OBEY’ prints above his bed."
~ lizabeth478
r/malelivingspace/Reddit
Rage Bomb
"I did some real estate photography on a home."
"It was a Massachusetts State Trooper's home. It was disturbing."
"A nice neighborhood, a nice home, clean and well maintained. Kids and wife photos decorating the walls and end tables."
"But I started noticing holes punched into walls—some of them plastered and repaired, some of them 'fresh'. Doors that had been splintered at the bottom from being kicked in. A couple doors that had padlocks on them that had been ripped out."
"There were just signs of rage everywhere I looked. It was disturbing, and I felt bad for the family."
~ parkerjh
Bartender Or Serial Killer
"A man with a collection of young women's ID cards."
~ FatFinPieSit
All Original
"Back in about 2015, I had a job at a high rise that had opened in the mid-1960s. One of the first residents was a young man. He moved in with his new furniture and lived there for the next 50 years before I met him."
"The bed was brown. Radiating from the center where it was deepest black-brown to the edges of the mattress where it was light brown. The pillow was nearly black. It was less mattress than it was a cloth covered set of collapsed springs."
"A number of the residents there were original to the building. From one lady I learned that he had never owned a set of sheets, slept in the nude, and had the same furniture set since he moved in, and that the mattress was also original."
"It was, by far, the filthiest bed I have ever seen."
~ shawslate
Rinse & Repeat
"Dish rack was in the sink and had black mold on it. They put clean dishes on it to dry.
"I was horrified."
"They also just put water in the baby bottles and let them soak then used them. Never actually washing the bottles."
"HORRIFIED."
~ sorrytooffnd
TP Shortage
"When I lived with a bunch of other dudes, I kept rebuying toilet paper and noticed none of the other roommates were."
"So, I just started keeping it in my closet instead and taking a roll to the bathroom when I needed to. They still didn't buy any."
"Visiting ladies were not enthused at the surprise, but I always offered them a roll... after they found out how gross the other guys were."
~ GovernmentSudden6134
Empathy
"One of my best friends from middle school invited me to spend the night one weekend and their house was so unbelievably nasty. It was more than just trash and dirty clothes all over the place."
"My friend’s older sister had a baby and they even had dirty diapers and food scraps throughout their apartment. Aside from that, there was some odd behavior from their mom who was gone pretty much the whole time we were there."
"We went swimming in their apartment pool that same weekend and my friend told me that her mom actually had a drug problem and she sometimes just wouldn’t see her for days at a time."
"So now I think any unusual amount of trash could indicate a serious issue someone there must really be going through in order for their house to be looking like that."
~ ABluntForcedDisTrama
Why Handshakes Are Ick
"No hand soap in the bathroom."
~ Myctic_Darling
"I lived in a 10 person house in college. We had 2 bathrooms. It sort of naturally split into girls' and guys' bathrooms, except for me who used the 'girls''."
"One night we’re drinking and a girl ends up using the guys' bathroom because the other was taken. She comes back and says, 'damn, you guys must use a ton of soap when you wash your hands'."
"Everyone looked confused. What?"
"She said she used that bathroom like a week or two ago and it was out of hand soap. She just used it, and it’s out again!"
"You could see it dawn on everyone’s faces."
"No Dawn on their hands, though..."
~ DigNitty
Here, Kitty, Kitty...
"Dirty litter boxes if they have cats, and I mean filthy."
~ Ophede
"Dirty litter boxes if they don’t have cats would be even more alarming."
~ todaytrip
Home Is Where The 🚩🚩🚩 Are
"I change the bathroom towels in our guest bathroom every Friday. One Friday after I finished, I told my son to go wipe up the urine he left on the seat and floor in the guest bathroom."
"I watched this imposter of my DNA wipe the urine up with a hand towel, then hang it back up on the towel rack, right in front of me."
"I've never wanted to disown a relative more in my life."
~ slightlydramatic
What's a red flag you observed in someone's home?