Propagation of offspring through sexual reproduction.
In analysing the ecological conditions of an animal population we have above all to focus our attention upon the most sensitive stages within the life cycle of the animal, that is, the period of breeding and larval development.1950, Gunnar Thorson, “Reproductive and Larval Ecology of Marine Bottom Invertebrates”, in Biological Reviews, volume 25, number 1, pages 1–45:
Plant breeding is always a numbers game.[…]The wild species we use are rich in genetic variation, and individual plants are highly heterozygous and do not breed true.2013 May-June, David Van Tassel, Lee DeHaan, “Wild Plants to the Rescue”, in American Scientist, volume 101, number 3, page 222:
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The act of insemination by natural or artificial means.
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The act of copulation in animals.
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The good manners regarded as characteristic of the aristocracy and conferred by heredity.
5
Nurture; education; formation of manners.
She had her breeding at my father's charge.c. 1604–1605 (date written), William Shakespeare, “All’s Well, that Ends Well”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act II, scene iii]:
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Descent; pedigree; extraction.
Your dog has good breeding.
Honest gentlemen, I know not your breeding.c. 1596–1599 (date written), William Shakespeare, “The Second Part of Henry the Fourth, […]. Epilogue.”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act V, scene iii]:
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LGBTSlang Ejaculation inside the rectum during bareback anal sex.
Etymology From Middle English bredyng, bredynge, from Old English *brēdende, from Proto-Germanic *brōdijandz, present participle of Proto-Germanic *brōdijaną (“to brood; breed”), equivalent to breed + -ing.
1
Of, relating to or used for breeding.
Your toothbrush is a breeding ground for bacteria.