Hyponymy and hypernymy

In linguistics, a hyponym (from Greek hupó, "under" and ónoma, "name") is a word or phrase whose semantic field is included within that of another word, its hyperonym or hypernym (from Greek hupér, "over" and ónoma, "name"). In simpler terms, a hyponym shares a type-of relationship with its hypernym. For example, pigeon, crow, eagle and seagull are all hyponyms of bird (their hyperonym); which, in turn, is a hyponym of animal.

Hyponymy shows the relationship between a generic term (hypernym) and a specific instance of it (hyponym). A hyponym is a word or phrase whose semantic field is more specific than its hypernym. The semantic field of a hypernym, also known as a superordinate, is broader than that of a hyponym. An approach to the relationship between hyponyms and hypernyms is to view a hypernym as consisting of hyponyms. This, however, becomes more difficult with abstract words such as imagine, understand and knowledge. While hyponyms are typically used to refer to nouns, it can also be used on other parts of speech. Like nouns, hyponyms in verbs are words that refer to a broad category of actions. For example, verbs such as stare, gaze, view and peer can also be considered hyponyms of the verb look.

Hypernyms and hyponyms are asymmetric. Hyponymy can be tested by substituting X and Y in the sentence ‘X is a kind of Y’ and determining if it makes sense. For example, ‘A screwdriver is a kind of tool’ makes sense but not ‘A tool is a kind of screwdriver’.

Strictly speaking, the meaning relation between hyponyms and hypernyms applies to lexical items of the same word class (or parts of speech), and holds between senses rather than words. For instance, the word screwdriver used in the previous example refers to the tool for turning a screw, and not to the drink made with vodka and orange juice.

Hyponymy is a transitive relation, if X is a hyponym of Y, and Y is a hyponym of Z, then X is a hyponym of Z. For example, violet is a hyponym of purple and purple is a hyponym of color; therefore violet is a hyponym of color. In addition, it should be noted that a word can be both a hypernym and a hyponym: for example purple is a hyponym of colour but itself is a hypernym of the broad spectrum of shades of purple between the range of crimson and violet.

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