defectiveness

adjective

1. having a defect or defects; imperfect; faulty
2. Gram. lacking some of the usual forms of inflection: “ought” is a defective verb
3. having a physical or mental defect; subnormal

Origin: ME & OFr defectif < LL defectivus

noun

1. ☆ a person with some physical or mental defect
2. Gram. a defective word