effectivity 

In manufacturing, which instances of a complicated product get a particular version of a part. Effectivity was coined at Boeing, in their old factory-control software, to identify a specific airplanes on the assembly line.

The redesigned part goes on this effectivity and all following ones.

effectivity by Tsamnami March 12, 2019

effectivity 

An idiotic modern word that has crept out of technical use in game theory to compete in pseudo-intellectual discourse with the real English word satisfying the same part of speech (effectiveness), which should be used instead in almost every case. Not to be confused with efficacy, which actually has a different meaning.

The effectivity of the word "effectivity" is nonexistent.

effectivity by phlux October 3, 2003

Effectivate 

Effectively activate something

"Wow man! You really effectivated your room! It looks great in this crib!"

Effectivate by The2ndPeriodWordCreator January 29, 2012