red flag
warning
the one-line answer
A warning sign in a person or relationship. Something is wrong.
Red flag means you noticed something that signals potential problems. In dating it means behavior that predicts this person or relationship will be harmful.
mainstream
Your coworker might use this word.
01 / in the wild
hear it move.
warning
he got angry when she spoke to another man. massive red flag.
That jealous controlling behavior is a serious warning sign.
03 / don't confuse
similar, not the same.
red flag
Red flag is a warning sign
vs
green-flag
Green flag is a positive sign.