Key word: chromosome.

The word chromosome has survived for over 100 years, because it succinctly defines what early cytologists were able to see with the most modern instrument of their time, a light microscope. It was introduced in a review that became widely known and was published almost simultaneously in German, English and French (Waldeyer 1888, 1889, 1890a, 1890b). In the late 19th century, these three languages were in strong competition for international status as the idiom of science. At the same time, Greek was also considered as a candidate for a nationalistically neutral language of science, and it seems more than coincidence that the word [Greek letters: see text] matches well the coherent Greek terminology used to describe the cell cycle in mitosis as well as meiosis. Emil Heitz (1935) maintained--in the face of reactionary German efforts to replace the term--that in using "the ineradicable word chromosome we think last of all that it indicates a body, that stains intensely,". Significantly, the key word is no longer restricted to eukaryotes, but has been readily adopted by microbial geneticists (Heidelberg el al. 2000) and acknowledged as defining the elementary unit of genomic partition.