Plurals and collective nouns

Many English scientific words have plurals that are a throwback to their language of origin. This is confusing to most North American's and therefore they are almost always incorectly used. The noun datum or its plural data is by far the most abused. There is no such thing as a single data point, it is a datum. Also, because it is plural, one says data were acquired. A data set is sometimes used to speak of a particular group of data points that have a common criteria. Table 5.2 is a list of preferred plurals of tricky scientific terms.

Table 5.2: Preferred plurals

Singular	Plural	Singular	Plural	Singular	Plural
analysis	analyses	errata	erratum	nucleus	nuclei
appendix	appendices	focus	foci	phenomenon	phenomena
axis	axes	formula	formulae	radius	radii
basis	bases	fulcrum	fulcra	stylus	styli
criterion	criteria	hypothesis	hypotheses	synthesis	syntheses
datum	data	matrix	matrices	thesis	theses
die	dice	medium	media