A fork of Rural Dictionary
The act of covertly sniffing a finger that has been inserted into a woman's vagina while making out for the purpose of determining if it is safe to proceed to oral sex.
I was going to munch her box, but I ran a litmus test, and it came back positive for stank, so I just bagged it and tagged it.
The act of following a questionable male or female to a public restroom to determine his/her actual gender.
"Chris" wore clothes that either sex could wear, had a haircut considered tolerable of both genders, and a voice that's indistinguishable between an angel or a scruffy Southerner. So Joe did the ol' litmus test and followed Chris to the office's bathroom.
The act of masturbating before deciding whether or not you will make social contact with a girl. Performing this test lets you make sure you're thinking with the correct head before proceeding to talk-to/meet-with a girl that you would otherwise regret making contact with.
After doing a jerkoff litmus test I realized that more than half of the female contacts in my phone are worthless.
Alice: Hey, did you the world is round?
Leon: Actually, it's round
Alice: I guess that just a typical litmus test then.