When people laugh by sucking air in over the sides of their tongue.

I’m confused by this and am having trouble making a mental model of what you’re describing. Given the thread topic, I’ll go ahead and admit that it’s irking me just slightly that I can’t figure out what you mean!

I can kinda picture laughing by pushing air out along the sides of your tongue, but sucking in? Whaaaa?? The only things I can conjure up that seems like it might be what you’re talking about are:

1. When someone makes clicking sounds that way, as is commonly done to call a horse. (We don't have any horse emojis?! thought for sure we had at least a Canadian Mounty acab.) It can also be thrown in during regular speech to delay or break up speaking in a similar way to an “uhm” or “ehr” though its use is uncommon this way. Sometimes it can be done as an expression of like “I gotcha”
2. The sound someone might make when suddenly, unexpectedly experiencing pain but doesn’t want to vocalize it. This is the kind of sound that results from sharply sucking in air and it’s somewhat like a hiss but with the sides of the tongue giving it more of an audible edge than a typical hiss. It always goes along with facial wincing from the pain. Or,
3. A sound very similar to 2 that some people make that’s actually like an expression of empathy at someone else’s physical pain, again like an auditory wince or cringe, just usually not as sharp or intense. It also sort of works with the “yikes” response to something:

But those don’t seem to line up with what I think you actually mean since none of those could be mistaken for laughter. Well, maybe the horse-call one could, possibly. Do you know of any easily found videos or the like that would demonstrate? Not to trigger your peeve.

I know this is a lot to write on something so trivial, but hey I’m having fun with it.

It’s always rich dudes doing that to sound more serious