Identifying word sense

We can identify the sense of a word by examining its relations with other words, the most basic forms of which are antonymy, synonymy, hyponymy and hypernomy.

Following Saussure, we can identify both paradigmatic (or substitutional) relationships between lexemes, involving their interchangeability in a particular context, and syntagmatic ones, involving their collocational possibilities: for example, one may toast bread in English but grill meat, despite the fact that the activity involved – exposure to heat – is essentially the same. Many of the terms used by semanticists to describe these sense relations are familiar, but employed in a more precise or specialized sense.

Sense relations between lexemes can be determined by specifying the truth conditions of the sentences in which they occur, i.e. the set of conditions that must necessarily be met for a sentence to be declared true. Consider, for example, the following two statements:

The cat ate the starling.

The cat ate a bird.

The first is true if – and only if (for which one writes, conventionally, iff) – the second is true also. This is an implicational (or one-way) relationship of entailment, from which we can deduce that all starlings have the property of being birds. Entailments must hold true in all possible worlds, and not just in a particular set of contexts. One can possibly imagine a science-fiction novel being written in which, as a result perhaps of a bizarre radioactive accident, all starlings were green, or had four legs, but it is impossible to imagine starlings not being birds. In cases of entailment of this kind, we can say that starling is a hyponym of bird, and that bird is the superordinate term or hypernym of starling, robin, jackdaw, ostrich, penguin and so on.

In many cases, psycholinguistic evidence suggests that a superordinate term is associated in a speaker’s mind with a prototype, i.e. a typical member of the category in question. For the superordinate term bird, for example, English speakers are more likely to think of robins as being typical of the bird class than, say, ostriches or penguins.