Flopmaster 

When a person makes plans and doesn't show up or does not follow through with the plans, they flop. This person becomes a flopmaster after not following through on a consistent level.

Alex: Hey man! I'm coming to visit you in three weeks!
Brandon: Okay, sweet!

*3 weeks later*

Alex: Yaaaaa. My mom said I have to work.
Brandon: Flopmaster.

Flopmaster by Sun-Maid Raisins September 21, 2012

flowmaster 

The most commonly found aftermarket cat-back exhaust system found on motor vehicles, especially domestic trucks and suv's. Generally popular for their relatively affordable price, large tip diameter, and loudass sound, they are one of the best selling exhaust systems to date. Although restrictive in design, most people think that the vehicles whom are equipped with such product is faster because they are fucking dumbshits when really it just chambers the exhuast flow to attain a certain frequency of sound that is relatively annoying and increases interior resonance. If you would like to be original with the sound of your car, don't buy a flowmaster. Flowmaster comes in several models, all of which suck my ass.

Dumbass: "hey did you hear that truck with the flows on it, it was fucking sick."

Me: "Fuck Flowmaster, they can kiss my ass."

flowmaster by Cali4niaBreez October 3, 2005

Flowmaster 

A girl who has got her period totally in check.

It is that time of the month again but my wife is a flowmaster.

Flowmaster by Angus McCracken January 25, 2020

Flowmaster 

A device used to enhance sound, as that of an internal-combustion engine. An influential part of the annoying urban car/truck exhaust family; a big brother to the whistle tip.

In an interview about irritating exhaust systems, Bubb Rubb says: Den u gots da flows; dey be tripping bout da flowmasters.

Yo Tyrese! me and Eric are go-in get dem flowmasters den we be blAzin nukka! sheeeeet!

Flowmaster by Jackson Nylander March 8, 2003

Flopmaster 

A male that is the master of making things floppy (loose) during intercourse.

Tom: "Who dated Susan last?"

Jim: "Larry did why?"

Tom: "She was so loose last night. Larry must be the flopmaster!"

Flopmaster by Tile December 16, 2007