diachronic / synchronic. (Gk, chronos, time; dia-, through, across; syn-, with, together). A diachronic study or analysis concerns itself with the evolution and change over time of that which is studied; it is roughly equivalent to historical. Thus diachronic linguistics is also known as historical linguistics. A synchronic study or analysis, in contrast, limits its concern to a particular moment of time. Thus synchronic linguistics takes a language as a working system at a particular point in time without concern for how it has developed to its present state. The extent to which synchronic study really does as it were take a frozen slice of history for study is itself not absolute: to talk of a system necessarily implies movement and interaction, and movement and interaction take place in time. Thus the synchronic studies of complete cultures carried out by the anthropologist Claude Levi-Strauss involved investigation of, for instance, symbolic exchanges which were consecutive rather than simultaneous, so that the element of temporal sequence is still present in such structuralist investigations.