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definitions

sterile

[ster-il or, esp. British, -ahyl]
adjective
  1. free from living germs or microorganisms; aseptic: sterile surgical instruments.
  2. incapable of producing offspring; not producing offspring.
  3. barren; not producing vegetation: sterile soil.
  4. Botany.
    1. noting a plant in which reproductive structures fail to develop.
    2. bearing no stamens or pistils.
  5. not productive of results, ideas, etc.; fruitless.

Origin of sterile

First recorded in 1545–55, sterile is from the Latin word sterilis unfruitful
Related formsster·ile·ly, adverbste·ril·i·ty [stuh-ril-i-tee] /stəˈrɪl ɪ ti/, ster·ile·ness, nounan·ti·ste·ril·i·ty, adjectivehalf-ster·ile, adjectivenon·ster·ile, adjectivenon·ster·ile·ly, adverbnon·ste·ril·i·ty, nounun·ster·ile, adjective
Can be confusedimpetus impotence sterilityimpotence sterility sterilized

Synonyms for sterile

2. infecund, unfruitful.

Antonyms for sterile

2, 3. fertile.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for unsterile

unsterile

adjective
  1. not free from living, esp pathogenic, microorganisms

sterile

adjective
  1. unable to produce offspring; infertile
  2. free from living, esp pathogenic, microorganisms; aseptic
  3. (of plants or their parts) not producing or bearing seeds, fruit, spores, stamens, or pistils
  4. lacking inspiration or vitality; fruitless
  5. economics, US (of gold) not being used to support credit creation or an increased money supply
Derived Formssterilely, adverbsterility (stɛˈrɪlɪtɪ), noun

Word Origin for sterile

C16: from Latin sterilis
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for unsterile

sterile

adj.

early 15c., "barren" (implied in sterility), from Middle French stérile "not producing fruit," from Latin sterilis "barren, unproductive," from PIE *ster- "sterile, barren" originally "stiff, rigid" (cf. Greek steresthai "be deprived of," steira "sterile," stereos "firm, solid, stiff, hard;" Sanskrit starih "a barren cow;" Old Church Slavonic sterica "a barren cow;" Gothic stairo "barren;" Old Norse stirtla "a barren cow"). See torpor. Originally in English with reference to soil; of females, from 1530s. The sense of "sterilized" is first recorded 1877.

Online Etymology Dictionary, © 2010 Douglas Harper
unsterile in Medicine

sterile

[stĕr′əl, -īl′]
adj.
  1. Not producing or incapable of producing offspring.
  2. Free from all live bacteria or other microorganisms and their spores.
Related formsster′ile•ness null n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
unsterile in Science

sterile

[stĕr′əl, stĕr′īl′]
  1. Not able to produce offspring, seeds, or fruit; unable to reproduce.
  2. Free from disease-causing microorganisms.
Related formssterility noun (stə-rĭl′ĭ-tē)
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.