preventive

• preventative

Borrowed from New Latin praeventīvus. Equivalent to prevent +‎ -ive.

• IPA^(key): /pɹɪˈvɛntɪv/

preventive (comparative more preventive, superlative most preventive)

1. Preventing, hindering, or acting as an obstacle to.
   • 1831, L[etitia] E[lizabeth] L[andon], chapter X, in Romance and Reality. […], volume II, London: Henry Colburn and Richard Bentley, […], →OCLC, page 146:

     ...and I sometimes think whether, like the ancient king, it would not be prudent to make an offering to destiny, and throw my set of emeralds into the lake." Emily could not but deprecate the emeralds being destined to any such preventive service;...

2. Carried out to deter military aggression.
3. Slowing the development of an illness; prophylactic.
   • 1650, Thomas Browne, Pseudodoxia Epidemica: […], 2nd edition, London: […] A[braham] Miller, for Edw[ard] Dod and Nath[aniel] Ekins, […], →OCLC:

     Physick is either curative or preventive.

4. (obsolete) Going before; preceding.
   • 1678, Ralph Cudworth, The True Intellectual System of the Universe:

     Any previous counsel or preventive understanding.

preventive (plural preventives)

1. (dated) A thing that prevents, hinders, or acts as an obstacle to.
   • 1856, Henry William Herbert, The Complete Manual for Young Sportsmen:

     Dogs should be warmly but airily housed; heartily, but not heatingly, fed — old Indian meal, mixed with oatmeal, suppawn, is the best general food, with a small quantity of salt, which is a preventive against worms […]

2. (dated) A thing that slows the development of an illness.
   • 1885, Cyprus guide and directory, page 82:

     Eaten with sugar yaourt is very palatable and refreshing in warm weather and is said to be a preventive of fever.

3. A contraceptive, especially a condom.

• prophylactic

• Although it is not mandatory, many speakers prefer to use preventive in adjective senses and preventative in noun senses.

preventive

1. feminine plural of preventivo