And it's SO specific that just reading that sentence, I knew exactly which meaning you meant, and which gesture. (Clicking the link to confirm was totally worth it though.) I've been on both ends of that gesture and it's always a hoot.

> DJs/audio techs/musicians have a set for talking in loud environments.

Whoah, really? I've improvised plenty, but I'm super curious if there's a standard set. You can always figure out "make louder", "make quieter", point at objects, mimic certain instruments. But it'd be nice to have more vocabulary beyond that.

http://www.preservationsound.com/2010/09/microphone-hand-sig...

https://www.cybercollege.com/hand_sigs.htm

And any orchestra can follow a conductor, baton or not.

Also re-reading this thread, I thought of the hand signals that every driver must learn in case their electrical turn signals go out, which are the same as bicyclist signals. Specific to the point of being enshrined in law.

I don't think "flipping the bird" is specific, it's either "I'm a jerk" or "I'm angry [with you]" but they both seem pretty wide ranging.

Pointing is really none specific, do you want it, want to look at it, want someone else to hold it, etc..

Military and crane operator signs seem like they're limited sign languages. Excellent example.

Driving is a good one, but it's 3 specific signs, and then pointing. I'm often annoyed that other drivers don't know BSL!

Thanks for illustrating the point, very helpful.