Like gaydar; but having the ability to sense if a homosexual male is a bear.
My grrdar is totally going off on that guy over there with the beard and Pixar hat. Woof!
Did you see that mom lose it with her three kids in the store? She totally had a momtrum!
When one of your friends is too chicken to add a new person that they're attracted to on a social website, and wants their friends to add the person along with him/her.
Well, what do you want us to do, gang-friend him?