Definition of "sterile"

sterile

/ˈstɛɹaɪl/

adjective
comparative more sterile, superlative most sterile
1. (not comparable) Unable to reproduce (or procreate).
  Quotations
  According to that Cabaliſticall Dogma: If Abram had not had this Letter [i.e., ה‎ (he)] added unto his Name he had remained fruitleſſe, and without the power of generation: […] So that being ſterill before, he received the power of generation from that meaſure and manſion in the Archetype; and was made conformable unto Binah.
  1658, Thomas Browne, “The Garden of Cyrus. […]. Chapter V.”, in Hydriotaphia, Urne-buriall, […] Together with The Garden of Cyrus, […], London: […] Hen[ry] Brome […]; reprinted as Hydriotaphia (The English Replicas), New York, N.Y.: Payson & Clarke Ltd., 1927, page 192
2. (figurative) Terse; lacking sentiment or emotional stimulation, as in a manner of speaking.
3. (figurative) Fruitless, uninspiring, or unproductive.
4. Germless; free from all living or viable microorganisms.
5. Free from dangerous objects, as a zone in an airport that can be only be entered via a security checkpoint.
6. (US, military) Of weapons: foreign-made and untraceable to the United States.
  Quotations
  An early CIA decision was to bring war surplus in Europe to the United States, rather than let it fall into the hands of left-wing movements. Some of the guns would also, it was reasoned, be useful as "sterile" weapons (foreign-made and untraceable to the United States) to be provided secretly to foreign friends.
  1980, Russell Warren Howe, Weapons: The International Game of Arms, Money and Diplomacy
  In addition to this rapid supply system, the US Army Counterinsurgency Support Office on Okinawa helped procure special equipment including rucksacks, special rations for irregular troops, 'sterile' weapons which could not be traced to the USA and other items not procurable through foreign channels.
  1990, Leroy Thompson, The US Army in Vietnam, page 111