One of the mysteries of the English language finally explained.
The fact of a marked inflectional category lacking certain features found in the corresponding unmarked category (e.g. the marked category of the future in French lacks a subjunctive, and is thus defective beside the present, which has both an indicative and a subjunctive); an instance of this.
1940s. From defective + -ation, after French défectivation (L. Hjelmslev, 1937 or earlier).
In this article we explore how to impress employers with a spot-on CV.