• WordNet 3.6
    • n synonymy the semantic relation that holds between two words that can (in a given context) express the same meaning
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Webster's Revised Unabridged Dictionary
    • Synonymy (Rhet) A figure by which synonymous words are used to amplify a discourse.
    • Synonymy A system of synonyms.
    • Synonymy The quality of being synonymous; sameness of meaning.
    • ***
Century Dictionary and Cyclopedia
    • n synonymy The quality of being synonymous, or of expressing the same meaning by different words.
    • n synonymy In rhetoric, a figure by which words of the same meaning are used to amplify a discourse.
    • n synonymy A thing of the same name.
    • n synonymy A system of synonyms; a collection of synonyms; also, the study of synonyms; the use of synonyms in expressing different shades of meaning; the discrimination of synonyms; especially, in natural history, the sifting of synonyms to determine the onyms. In botany and zoölogy the synonymy of a species of plant or animal, in the concrete, is a list of the several different names which have been applied to it by its various describers or classifiers, implying on the synonymist's part the discrimination not only of the synonyms of the species, but of the homonyms of related species, for the especial purpose of determining the onym of each species. Thus, Falco fuscus and Falco obscurus may be synonyms of one and the same species of falcon, yet Falco fuscus may be a homonym of two different species of falcon, and it may be that neither name is the onym of either of these species. Synonymy in natural history has become of late years so extensive and so intricate that probably no naturalist has mastered the subject beyond the line of some one narrow specialty. Synonymatic lists for single species extending over several pages of an ordinary book are of no infrequent occurrence. See synonym, 3.
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Chambers's Twentieth Century Dictionary
    • n Synonymy the quality of being synonymous: a rhetorical figure by which synonymous words are used
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Webster's Revised Unabridged Dictionary
L. synonymia, Gr. a synonym: cf. F. synonymie,
Chambers's Twentieth Century Dictionary
Gr. synōnymonsyn, with, onoma, a name.


In literature:

This being a decisive specific character the synonymy prior to Rostafinski is somewhat uncertain.
"The North American Slime-Moulds" by Thomas H. (Thomas Huston) MacBride
References cited only in the synonymies are not listed in the Literature Cited.
"The Amphibians and Reptiles of Michoacán, México" by William E. Duellman
Steinschneider has declared this book to be one of the most important works in the field of Synonymies.
"The Popes and Science" by James J. Walsh
Sueciae, anno 1732 instituta, additis synonymis, &c. Amstelod.
"Lives of Eminent Zoologists, from Aristotle to Linnæus" by William MacGillivray
Literature reports are cited in the synonymy.
"Geographic Variation in the North American Cyprinid Fish, Hybopsis gracilis" by Leonard J. Olund
The species are very variously understood by European botanists, and are much confused, as well as the synonymy.
"The Manual of the Botany of the Northern United States" by Asa Gray

In news:

So essential to our concept of bodily existence, it is the synonymy of life and death.
Latent Semantic Indexing (LSI) has been shown to be effective in recovering from synonymy and polysemy in text retrieval applications.

In science:

Zipf ’s law and avoidance of excessive synonymy.
Information content versus word length in random typing
In addition, since ‘synonymy’ shows a stronger relation than ‘similarity’, and since ‘similar words’ are stronger than ‘see also’ words, we assign different weights to them.
Opinion Polarity Identification through Adjectives
Cohesion (proper name anaphora, reiteration, synonymy, and hypernymy) and coherence (based on Rhetorical Structure Theory [Mann and Thompson, 1987]) relations between sentences were used in [Mani et al., 1998] to define salience.
MUDOS-NG: Multi-document Summaries Using N-gram Graphs (Tech Report)
That is why contextual meaning is linked with ambiguity and with the sense of words. Ambiguity is mainly caused by polysemy (one term with different meanings) and synonymy (different words for the same meaning).
Quantum-like Tests for Contextual Querying
Cohesion is brought about by linguistic devices such as repetition, synonymy, anaphora, and ellipsis.
Machine Learning of Generic and User-Focused Summarization