The following are expressions I have encountered in my various stints in the food service industry. Like all forms of slang, these are specific to both region and speakers.
Walking in means that a new ticket just came in. As in "Three house salads walking in."
All day means that there are X number of orders for a particular menu item in a given period of time.
HOT SOUP! indicates that the speaker is carrying a container of piping hot soup. If you hear this, stand back!
S.O.D. is an acronym meaning soup of the day.
Right behind you is usually spoken softly by someone unseen carrying something heavy or delicate. This is a request for others in the area to stand still or step aside.
On your left/right similar to the above.
Corner means that someone is coming around the corner carrying stuff. Look out!
On the fly means to expedite an order or correction as the customer is waiting and/or impatient.
86 may mean that the kitchen is out of a particular menu option or to cancel an order.
Black and blue means meat that is cooked rare on the inside but charred on the outside.
In the weeds means that a line cook has more tickets than they can handle without the customers having to wait too long.
Dish pit is the corner of the kitchen where dirty dishes and utensils are kept and cleaned.
Hot pot indicates that something just went from the stove to the dish pit and should be allowed to cool before handling with bare hands.
Order up means that food is ready to be served.
if you know of any others, /msg me and i'll add 'em on. —and if you find yourself about to embark on the grand adventure that is working food service, do rememeber to keep to the right
as much as possible.