Some images are objective and stable and are not influenced by a particular situation. Such images are referred to as 'concepts'. Concepts provide the information necessary to discriminate between the various meanings of the words contained in the English-Japanese Bilingual Dictionary. The concepts are similar to the word senses noted in paper-based dictionaries but differ in the sense that they are not language dependent. In addition to the concept identifier, content words are also supplied with a headconcept and a concept explication.
Content words are words that have independent and concrete concepts.
Content words in English are nouns, verbs, adjectives, adverbs, and phrasals. Headconcepts are described in both English and Japanese by a headword that best represents the concept. For English-specific concepts where a suitable representative Japanese headword does not exist however, an Japanese headconcept is not provided. The concept explication is a written explanation of the concept, and is provided in order to help people distinguish the various concept of a word. For detailed information regarding concepts, refer to Chapter 4 Concept Dictionary.