THE STRUCTURE OF DEICTIC DAY-NAME SYSTEMS Jan Tent Abstract. This paper is a cross-linguistic study examining the structure of deictic day-name systems of 157 of the world's languages. Most of these systems reveal a recurring structural symmetry in the number of diurnal units identified either side of `today'. As well as this type of numerical symmetry, most languages exhibit a morphological symmetry, and several a lexical symmetry. A small number of languages have numerically and/or morphologically asymmetrical systems. The nature of these symmetries and asymmetries is briefly explored. 1. Introduction In the discussion of calendric units, in his now famous Santa Cruz Lectures on Deixis, Charles Fillmore (1975:47) mentions that many languages have a rich set of lexicalisations for deictic day-names. He refers to Persian (Farsi) which has a deictic day-name system that names two days ahead of and four days back from `today'; Japanese and Russian which both have systems extending three days either side of `today'; Vietnamese with a system extending three days ahead of `today' and four days back; and Chinantec with a deictic day-name system that names four days on either side of `today'. In this article I shall examine such systems in more detail to see whether they reveal any universal characteristics in structure and composition. The study is based on a corpus of the deictic day-name inventories of 157 unsystematically sampled, but genetically diverse languages. 1 The number of day-names per system ranges from 3 to 13, and the morphological complexity can range from simple monomorphemic lexemes to complex polymorphemic expressions. Most languages in the sample reveal a high degree structural and morphological symmetry in their systems, and almost two-thirds of the languages have a day-name system consisting of 5 items (i.e. two days named either side of `today'). 2 Deictic day-names are nouns or time adverbials which name, or identify, diurnal spans in relation to the `coding time' (CT) of an utterance (i.e. the Studia Linguistica 52(2) 1998, pp. 112±148. # The Editorial Board of Studia Linguistica 1998. Published by Blackwell Publishers, 108 Cowley Road, Oxford OX4 1JF, UK, and 350 Main Street, Malden, MA 02148, USA 1 These were obtained via the generous replies to requests for data through the electronic discussion lists LINGUIST-List and INFO-SIL; personal communications with linguists, and a few non-linguist native speakers; and a number of grammars and dictionaries. In general I have accepted on good faith the assessments, descriptions, orthographical repre- sentations of day-name systems offered by my sources, though veryoccasionally I have had to make my own assessment on minor points. Tables cataloguing the languages in the corpus, theirgenetic affiliation and region where spoken are given in the appendix. 2 Any generalisations made or conclusions drawn regarding the structure of day-name systems refer only to those systems in my corpus. It is fully appreciated that day-name systems not mentioned in this survey may behave quite differently.