Flip knife 

One of those folding lock blade knives with the little stud on the blade that allows a person to open it with only one hand. When modified so that it can be opened simply by a flick of the wrist(sometimes with some thumb pressure), it becomes a flip knife. In some states it's considered the same thing as a switchblade

Everbody knows T packs a flip knife, thats why the pigs are on him all the time.

Flip knife by Wolf89 December 25, 2005

Flip-Knife 

Someone looked up synonyms for the words “switch” and “blade” and rebranded the switch-blade to make it legal

“Yo dude is that a switchblade?”
“Nah man, this is a flip-knife”
“Well, what’s the difference”
“What do you mean?”
“Is there a difference between a switchblade and a flip-knife?
“I don’t understand the question”

Flip-Knife by CrankinCraig April 26, 2021