Tag Archives: definitions

Efficacy vs. Efficiency

I often get confused between the definitions of the following 2 terms and when to use them:

Efficacy = capacity to produce an effect; effectiveness of something; doing the right thing.

Efficiency = extent/amount of time or effort used for an intended task or purpose; competency in something; doing things right.

e.g. (?) = The efficiency of my blog writing is lacking, and so is its efficacy.

Yep. I just confused myself a bit more.