efficascious 

Adj. describing a wildly unpopular person who scrutinizes over every move you make.

"Did the substitute write you up for talking?"

"yeah and she's an efficascious bitch for doing it, too."

efficascious by tenahj March 9, 2008

efficacious 

A douchey way of saying effective.

When trying to impress with his vocabulary by using the word 'efficacious' rather than 'effective', the man was actually more efficacious at sounding like an ass.

efficacious by dgeezy May 13, 2015

efficacious 

An adjective (descriptive word):

Describing thing, or person, producing, or sure to produce, desired effect.

"Efficaciously" (adverb) describing the behaviour of act in such a manner as to effect the desired effect.
I may help to understand that the Latin root for these words is the same as that for "Efficient".

Asprin is truly "efficacious" for the treatment of headaches.

I've never known a teacher to be so consistent in dealing so "efficaciously" with problem students, as he does.

efficacious by Sparticus774 May 27, 2014