When one changes lanes on a freeway or highway without hitting any of the reflecting bumps in the middle of the road.
A merge-swish can also be applied when passing someone on a two lane road, provided you do not hit any of the reflective bumps in the middle of said road...or the oncoming traffic.
Bill Blimey: "Man, I just changed lanes three times and totally merge-swished every time. It was nothing but line!"
Tom Toppover: "That's weak sauce. You should have seen the merge-swish I pulled off last night while passing that big rig."
An shocking and unexpected bollock and cock washing bidet event caused by the accidental activation of an automatic or manual flush whilst seated peacefully in a public toilet.
Me: It was horrendous; The flush came rushing out of nowhere like an arctic tsunami and gave me a chilling Witches Swish .
Therapist: ?
Me: You know? When you flush your nuts by mistake.
Therapist: I think 'm gonna need therapy.
Swish is a fucking horrible drink that is made by taking a barrel that any kind of hard liquer has been aged in, fillin it up with water, and waiting for it soak up all the liquer juices, it looks like shit, smells like shit and tastes like shit, it is fucking nearly impossible to swallow, but it gets you insanely drunk and is cheap as fuck. The biggest downside of it is that it can blind or kill you, but the price is right!
guy 1:"What you drinkin tonight?"
guy 2:"Swish, it's fucking cheap."
guy 1:"That shit is nasty."
guy 2:"Ye, but it gets your fuckin DRUNK bud."