defective

Etymology

From Middle English defectif, defective, from Old French defectif, from Late Latin dēfectīvus.

adj

1. Having one or more defects.
   It is likely that the long evolutionary trajectory of Mycoplasma went from a reductive autotroph to oxidative heterotroph to a cell-wall–defective degenerate parasite. This evolutionary trajectory assumes the simplicity to complexity route of biogenesis, a point of view that is not universally accepted. 2013 March, Harold J. Morowitz, “The Smallest Cell”, in American Scientist, volume 101, number 2, United States: Sigma Xi, →ISSN, →OCLC, archived from the original on 2017-01-04, page 83
2. (grammar, of a lexeme, especially a verb) Lacking some forms; e.g., having only one tense or being usable only in the third person.
3. (Arabic grammar, of a verb) Having a root whose final consonant is weak (ي, و, or ء).
4. (orthography, of a script) Not capable of representing all the phonemic distinctions of a language it is used to write.
5. (chiefly of abjad script) Spelled without matres lectionis, for example אמץ (ómets, “courage”) as opposed to the plene spelling אומץ where the letter vav ⟨ו⟩ indicates the vowel o.

adv

1. (chiefly of abjad script) Without matres lectionis (letters indicating vowels) written out.
   For the sake of comparison, note the distribution of these spellings in some other Hebrew sources: in the MT the vowel o after the first consonant of the root is written defective in approximately 3,600 cases as against 850 cases of plene spelling. 2013, Gregor Geiger, Plene Writing of the Qōṭēl Pattern in the Dead Sea Scrolls

noun

1. A person or thing considered to be defective.
   It is an offence, subject to the exception mentioned in this section, for a person to procure a woman who is a defective to have unlawful sexual intercourse in any part of the world. 1956, Parliament of the United Kingdom, “Part I, section 9(1)”, in Sexual Offences Act 1956, page 3
   There were many more kinds of mental institutions at mid-century, ones for "mental defectives and epileptics" and the mentally retarded, psychiatric wards in veterans hospitals, as well as "psychopathic" and private mental hospitals. January 15, 2007, Bernard E. Harcourt, “The Mentally Ill, Behind Bars”, in New York Times
2. (chiefly of abjad script) A word written without matres lectionis (letters indicating vowels).
   Thus, in the Pentateuch and in the earlier prophets the plenes are counted, whilst in the later prophets the defectives are enumerated. 2011, Christian D. Ginsburg, Jacob Ben Chajim Ibn Adonijah's Introduction to the Rabbinic Bible: Hebrew and English with Explanatory Notes