1 My focus is entirely on the substantive vocabulary, typically nouns, verbs, and adjective, which have a conceptual meaning that is stable but context-sensitive and flexible, with ever-evolving families of related senses. Grammatical or functional items are quite different -they are small closed sets of items e.g. inflectional affixes (for number, tense, aspect), derivational affixes (for nominalization, verbalization, etc.), articles, demonstratives, quantifiers, modals and others. These are of critical importance to the meaning of the structures in which they occur (sentences, phrases, sometimes 'words'), but their semantics is quite different from that of the substantive items -it is rigid, formal, non-conceptual -and has to be given a separate treatment.