The Rice University Neologisms Database

To swim the stroke of butterfly with such fatigue or lack of effort that the upper body and arms are brought down from their top position in the stroke cycle solely by the swimmer’s body weight in an uncontrolled and heavy manner. This word is used to describe the swimming stroke of butterfly with such poor form or with such exhaustion that it could be described as ‘flumping.’ Butterflump, butterflumps and butterflumping are specialised words in the swimming community, and more specifically I have only ever heard them used by people in my swimming club. The reason for coinage was that the stroke was performed so badly that it no longer satisfied the definition of swimming butterfly (a graceful stroke where the swimmer glides through the water seemingly effortlessly) and an alternative verb was needed. So, in an effort to express my disgust to a teammate, the word butterflump was born. As far as I know I made this word up as search engines did not show any results for this word.