You may wonder whether you have missed something, but no, you have
not. 'Etyrminology' is just an invention to draw your attention to this
column, where I want to analyse the etymological background of terms
- in other words, their derivation, which in most instances is from
Latin and Greek words - used in the veterinary and biomedical sciences.
Although I do not want to be too catholic - scientific terminology is
also alive and evolving - I will indicate the misuse of words every
now and then.
If you have a term and want to know its roots, or, alternatively, if
you know the derivation of a word and you think it interesting, do drop
us a line.
acetabulum = socket of the hip joint; from L. acetum, vinegar. The term refers to the shape of a small bowl used in Roman antiquity to contain vinegar (most often), and other fluids. The term is used in biology for similar structures in fungi, lichens, the suction cups of gastropods, etc.
bacillus, (pl. bacilli) = rod-shaped bacterium (pl. bacteria); reference to the stick or rod (baculum) is also found in 'baculovirus'. Bacillus is actually the diminutive form of the word.
calculus = stone, concrement, like in c. dentalis (tartar), c.felleus (gall stone), c.renalis (kidney stone), c.salivalis (salivary gland calculus, sialolith), c.vesicae (bladder stone, urolith). In Roman antiquity, calculi referred to the pieces used for board games, and their use for adding and subtracting led to the term 'to calculate'.
data = findings, observations, experimental results, facts, details; from L. dare, to give. The participle 'datum' refers to something given, which in many European languages is the calendar date (still used as 'datum' in German and Dutch, for example). Most Latin nouns ending in 'um' are of neutral gender, the nominative plural forms of which end in 'a'. In other words, 'data' is a plural form of the word 'datum'. It is, therefore, incorrect to write 'Our data shows..'.
eradicate = cleanse, eliminate, erase, purge, remove; from L. ex, out; and radix, root. The metaphor of pulling a weed out, 'roots and all', expresses the intention that it should never come back. As an epidemiological concept, eradication had its first success in medicine with smallpox (1972), which now serves as an example for poliomyelitis and measles, with completion of their eradication planned for the near future. By definition, eradication is worldwide, the result of a concerted international action, it has a deadline, and is attempted only in the absence of a reservoir host. It is, therefore, erroneous to speak, for example, of '... the partial eradication of classical swine fever from the Netherlands'.
pathogenic = causing disease; from G. pathos, suffering, and genesis, creation. In microbiology, the term is used to describe the relationship between an agent and its host species: '... rabies virus is pathogenic for the dog', or 'smallpox virus is a human pathogen'. However, 'pathogenic' and 'virulent' are often used synonymously, which is incorrect. Virulence is the disease-causing property of a given strain of a pathogen, for example, '... the Flury strain of rabies virus is avirulent for dogs'. Fuzzy usage has led to designations like 'intracerebral pathogenicity index' for strains of Newcastle disease virus - it is obviously the degree of virulence that is measured for this pathogen.