Why has the term 'biotechnology' been so ambiguous, while hopes for the subject have been so high? Exploring biotechnology's historic role as a 'boundary object' between engineering and biology offers an explanation. The word is shown to have been interpreted in a variety of ways since the beginning of the century. Here the translations and negotiations over its identity are uncovered, showing that the words Biotechnik and Biotechnologie were pioneered around World War I, principally in Denmark, Germany and Hungary. Those ideas were used and modified in the writings and institutions of engineers and biologists in Britian, Sweden and the USA. The 1960s are identified as the period in which biotechnology acquired a single identify, but alternative meanings were in conflict and then merged in the 1970s and 1980s. The analysis suggests that the concept of a 'biotechnology' is deeply entrenched in twentieth-century culture, and that current debates over regulation can be seen in terms of uncertainties over the proper boundary between engineering and biology.
